diff --git a/htdocs/comm/propal/card.php b/htdocs/comm/propal/card.php
index 0c9d97fc299..4ee029ee8e8 100644
--- a/htdocs/comm/propal/card.php
+++ b/htdocs/comm/propal/card.php
@@ -210,7 +210,7 @@ if (empty($reshook))
 			$outputlangs = $langs;
 			if (! empty($conf->global->MAIN_MULTILANGS)) {
 				$outputlangs = new Translate("", $conf);
-				$newlang = (GETPOST('lang_id') ? GETPOST('lang_id') : $object->thirdparty->default_lang);
+				$newlang = (GETPOST('lang_id','aZ09') ? GETPOST('lang_id','aZ09') : $object->thirdparty->default_lang);
 				$outputlangs->setDefaultLang($newlang);
 			}
 			$ret = $object->fetch($id); // Reload to get new records
@@ -234,7 +234,7 @@ if (empty($reshook))
 			{
 				$outputlangs = $langs;
 				$newlang = '';
-				if ($conf->global->MAIN_MULTILANGS && empty($newlang) && GETPOST('lang_id')) $newlang = GETPOST('lang_id','alpha');
+				if ($conf->global->MAIN_MULTILANGS && empty($newlang) && GETPOST('lang_id','aZ09')) $newlang = GETPOST('lang_id','aZ09');
 				if ($conf->global->MAIN_MULTILANGS && empty($newlang))	$newlang = $object->thirdparty->default_lang;
 				if (! empty($newlang)) {
 					$outputlangs = new Translate("", $conf);
@@ -558,7 +558,7 @@ if (empty($reshook))
 				    	{
 				    		$outputlangs = $langs;
 				    		$newlang = '';
-				    		if ($conf->global->MAIN_MULTILANGS && empty($newlang) && GETPOST('lang_id')) $newlang = GETPOST('lang_id','alpha');
+				    		if ($conf->global->MAIN_MULTILANGS && empty($newlang) && GETPOST('lang_id','aZ09')) $newlang = GETPOST('lang_id','aZ09');
 				    		if ($conf->global->MAIN_MULTILANGS && empty($newlang))	$newlang = $object->thirdparty->default_lang;
 				    		if (! empty($newlang)) {
 				    			$outputlangs = new Translate("", $conf);
@@ -663,7 +663,7 @@ if (empty($reshook))
 			$outputlangs = $langs;
 			if (! empty($conf->global->MAIN_MULTILANGS)) {
 				$outputlangs = new Translate("", $conf);
-				$newlang = (GETPOST('lang_id') ? GETPOST('lang_id') : $object->thirdparty->default_lang);
+				$newlang = (GETPOST('lang_id','aZ09') ? GETPOST('lang_id','aZ09') : $object->thirdparty->default_lang);
 				$outputlangs->setDefaultLang($newlang);
 			}
 			$ret = $object->fetch($id); // Reload to get new records
@@ -833,8 +833,8 @@ if (empty($reshook))
 				if (! empty($conf->global->MAIN_MULTILANGS) && ! empty($conf->global->PRODUIT_TEXTS_IN_THIRDPARTY_LANGUAGE)) {
 					$outputlangs = $langs;
 					$newlang = '';
-					if (empty($newlang) && GETPOST('lang_id'))
-						$newlang = GETPOST('lang_id');
+					if (empty($newlang) && GETPOST('lang_id','aZ09'))
+						$newlang = GETPOST('lang_id','aZ09');
 					if (empty($newlang))
 						$newlang = $object->thirdparty->default_lang;
 					if (! empty($newlang)) {
@@ -920,7 +920,7 @@ if (empty($reshook))
 						$outputlangs = $langs;
 						if (! empty($conf->global->MAIN_MULTILANGS)) {
 							$outputlangs = new Translate("", $conf);
-							$newlang = (GETPOST('lang_id') ? GETPOST('lang_id') : $object->thirdparty->default_lang);
+							$newlang = (GETPOST('lang_id','aZ09') ? GETPOST('lang_id','aZ09') : $object->thirdparty->default_lang);
 							$outputlangs->setDefaultLang($newlang);
 						}
 						$ret = $object->fetch($id); // Reload to get new records
@@ -1065,7 +1065,7 @@ if (empty($reshook))
 					$outputlangs = $langs;
 					if (! empty($conf->global->MAIN_MULTILANGS)) {
 						$outputlangs = new Translate("", $conf);
-						$newlang = (GETPOST('lang_id') ? GETPOST('lang_id') : $object->thirdparty->default_lang);
+						$newlang = (GETPOST('lang_id','aZ09') ? GETPOST('lang_id','aZ09') : $object->thirdparty->default_lang);
 						$outputlangs->setDefaultLang($newlang);
 					}
 					$ret = $object->fetch($id); // Reload to get new records
diff --git a/htdocs/comm/propal/class/propal.class.php b/htdocs/comm/propal/class/propal.class.php
index 11aa3c95b95..d7f2411f615 100644
--- a/htdocs/comm/propal/class/propal.class.php
+++ b/htdocs/comm/propal/class/propal.class.php
@@ -2305,7 +2305,7 @@ class Propal extends CommonObject
                	if (! empty($conf->global->MAIN_MULTILANGS))
                	{
                		$outputlangs = new Translate("",$conf);
-               		$newlang=(GETPOST('lang_id') ? GETPOST('lang_id') : $this->thirdparty->default_lang);
+               		$newlang=(GETPOST('lang_id','aZ09') ? GETPOST('lang_id','aZ09') : $this->thirdparty->default_lang);
                		$outputlangs->setDefaultLang($newlang);
                	}
                	//$ret=$object->fetch($id);    // Reload to get new records
diff --git a/htdocs/commande/card.php b/htdocs/commande/card.php
index a10de641ea1..826046db3ee 100644
--- a/htdocs/commande/card.php
+++ b/htdocs/commande/card.php
@@ -208,8 +208,8 @@ if (empty($reshook))
 			// Define output language
 			$outputlangs = $langs;
 			$newlang = '';
-			if ($conf->global->MAIN_MULTILANGS && empty($newlang) && GETPOST('lang_id'))
-				$newlang = GETPOST('lang_id');
+			if ($conf->global->MAIN_MULTILANGS && empty($newlang) && GETPOST('lang_id','aZ09'))
+				$newlang = GETPOST('lang_id','aZ09');
 			if ($conf->global->MAIN_MULTILANGS && empty($newlang))
 				$newlang = $object->thirdparty->default_lang;
 			if (! empty($newlang)) {
@@ -801,8 +801,8 @@ if (empty($reshook))
 				if (! empty($conf->global->MAIN_MULTILANGS) && ! empty($conf->global->PRODUIT_TEXTS_IN_THIRDPARTY_LANGUAGE)) {
 					$outputlangs = $langs;
 					$newlang = '';
-					if (empty($newlang) && GETPOST('lang_id'))
-						$newlang = GETPOST('lang_id');
+					if (empty($newlang) && GETPOST('lang_id','aZ09'))
+						$newlang = GETPOST('lang_id','aZ09');
 					if (empty($newlang))
 						$newlang = $object->thirdparty->default_lang;
 					if (! empty($newlang)) {
@@ -1015,8 +1015,8 @@ if (empty($reshook))
 					// Define output language
 					$outputlangs = $langs;
 					$newlang = '';
-					if ($conf->global->MAIN_MULTILANGS && empty($newlang) && GETPOST('lang_id'))
-						$newlang = GETPOST('lang_id');
+					if ($conf->global->MAIN_MULTILANGS && empty($newlang) && GETPOST('lang_id','aZ09'))
+						$newlang = GETPOST('lang_id','aZ09');
 					if ($conf->global->MAIN_MULTILANGS && empty($newlang))
 						$newlang = $object->thirdparty->default_lang;
 					if (! empty($newlang)) {
@@ -1102,7 +1102,7 @@ if (empty($reshook))
 				{
 					$outputlangs = $langs;
 					$newlang = '';
-					if ($conf->global->MAIN_MULTILANGS && empty($newlang) && GETPOST('lang_id')) $newlang = GETPOST('lang_id','alpha');
+					if ($conf->global->MAIN_MULTILANGS && empty($newlang) && GETPOST('lang_id','aZ09')) $newlang = GETPOST('lang_id','aZ09');
 					if ($conf->global->MAIN_MULTILANGS && empty($newlang))	$newlang = $object->thirdparty->default_lang;
 					if (! empty($newlang)) {
 						$outputlangs = new Translate("", $conf);
@@ -1155,7 +1155,7 @@ if (empty($reshook))
 				{
 					$outputlangs = $langs;
 					$newlang = '';
-					if ($conf->global->MAIN_MULTILANGS && empty($newlang) && GETPOST('lang_id')) $newlang = GETPOST('lang_id','alpha');
+					if ($conf->global->MAIN_MULTILANGS && empty($newlang) && GETPOST('lang_id','aZ09')) $newlang = GETPOST('lang_id','aZ09');
 					if ($conf->global->MAIN_MULTILANGS && empty($newlang))	$newlang = $object->thirdparty->default_lang;
 					if (! empty($newlang)) {
 						$outputlangs = new Translate("", $conf);
diff --git a/htdocs/compta/facture/card.php b/htdocs/compta/facture/card.php
index 6c2ab5786b7..dd89ae944ef 100644
--- a/htdocs/compta/facture/card.php
+++ b/htdocs/compta/facture/card.php
@@ -464,7 +464,7 @@ if (empty($reshook))
 				{
 					$outputlangs = $langs;
 					$newlang = '';
-					if ($conf->global->MAIN_MULTILANGS && empty($newlang) && GETPOST('lang_id')) $newlang = GETPOST('lang_id','alpha');
+					if ($conf->global->MAIN_MULTILANGS && empty($newlang) && GETPOST('lang_id','aZ09')) $newlang = GETPOST('lang_id','aZ09');
 					if ($conf->global->MAIN_MULTILANGS && empty($newlang))	$newlang = $object->thirdparty->default_lang;
 					if (! empty($newlang)) {
 						$outputlangs = new Translate("", $conf);
@@ -550,7 +550,7 @@ if (empty($reshook))
 				{
 					$outputlangs = $langs;
 					$newlang = '';
-					if ($conf->global->MAIN_MULTILANGS && empty($newlang) && GETPOST('lang_id')) $newlang = GETPOST('lang_id','alpha');
+					if ($conf->global->MAIN_MULTILANGS && empty($newlang) && GETPOST('lang_id','aZ09')) $newlang = GETPOST('lang_id','aZ09');
 					if ($conf->global->MAIN_MULTILANGS && empty($newlang))	$newlang = $object->thirdparty->default_lang;
 					if (! empty($newlang)) {
 						$outputlangs = new Translate("", $conf);
@@ -1368,7 +1368,7 @@ if (empty($reshook))
 			{
 				$outputlangs = $langs;
 				$newlang = '';
-				if ($conf->global->MAIN_MULTILANGS && empty($newlang) && GETPOST('lang_id')) $newlang = GETPOST('lang_id','alpha');
+				if ($conf->global->MAIN_MULTILANGS && empty($newlang) && GETPOST('lang_id','aZ09')) $newlang = GETPOST('lang_id','aZ09');
 				if ($conf->global->MAIN_MULTILANGS && empty($newlang))	$newlang = $object->thirdparty->default_lang;
 				if (! empty($newlang)) {
 					$outputlangs = new Translate("", $conf);
@@ -1583,8 +1583,8 @@ if (empty($reshook))
 				if (! empty($conf->global->MAIN_MULTILANGS) && ! empty($conf->global->PRODUIT_TEXTS_IN_THIRDPARTY_LANGUAGE)) {
 					$outputlangs = $langs;
 					$newlang = '';
-					if (empty($newlang) && GETPOST('lang_id'))
-						$newlang = GETPOST('lang_id');
+					if (empty($newlang) && GETPOST('lang_id','aZ09'))
+						$newlang = GETPOST('lang_id','aZ09');
 					if (empty($newlang))
 						$newlang = $object->thirdparty->default_lang;
 					if (! empty($newlang)) {
@@ -1653,7 +1653,7 @@ if (empty($reshook))
 					{
 						$outputlangs = $langs;
 						$newlang = '';
-						if ($conf->global->MAIN_MULTILANGS && empty($newlang) && GETPOST('lang_id')) $newlang = GETPOST('lang_id','alpha');
+						if ($conf->global->MAIN_MULTILANGS && empty($newlang) && GETPOST('lang_id','aZ09')) $newlang = GETPOST('lang_id','aZ09');
 						if ($conf->global->MAIN_MULTILANGS && empty($newlang))	$newlang = $object->thirdparty->default_lang;
 						if (! empty($newlang)) {
 							$outputlangs = new Translate("", $conf);
@@ -1829,8 +1829,8 @@ if (empty($reshook))
 					// Define output language
 					$outputlangs = $langs;
 					$newlang = '';
-					if ($conf->global->MAIN_MULTILANGS && empty($newlang) && GETPOST('lang_id'))
-						$newlang = GETPOST('lang_id');
+					if ($conf->global->MAIN_MULTILANGS && empty($newlang) && GETPOST('lang_id','aZ09'))
+						$newlang = GETPOST('lang_id','aZ09');
 					if ($conf->global->MAIN_MULTILANGS && empty($newlang))
 						$newlang = $object->thirdparty->default_lang;
 					if (! empty($newlang)) {
diff --git a/htdocs/compta/facture/fiche-rec.php b/htdocs/compta/facture/fiche-rec.php
index 221167a485a..22306e498f2 100644
--- a/htdocs/compta/facture/fiche-rec.php
+++ b/htdocs/compta/facture/fiche-rec.php
@@ -545,8 +545,8 @@ if (empty($reshook))
     		{
     			$outputlangs = $langs;
     			$newlang = '';
-    			if (empty($newlang) && GETPOST('lang_id'))
-    				$newlang = GETPOST('lang_id');
+    			if (empty($newlang) && GETPOST('lang_id','aZ09'))
+    				$newlang = GETPOST('lang_id','aZ09');
     			if (empty($newlang))
     				$newlang = $object->thirdparty->default_lang;
     			if (! empty($newlang))
@@ -625,7 +625,7 @@ if (empty($reshook))
     			    // Define output language
     			    $outputlangs = $langs;
     			    $newlang = '';
-    			    if ($conf->global->MAIN_MULTILANGS && empty($newlang) && GETPOST('lang_id')) $newlang = GETPOST('lang_id','alpha');
+    			    if ($conf->global->MAIN_MULTILANGS && empty($newlang) && GETPOST('lang_id','aZ09')) $newlang = GETPOST('lang_id','aZ09');
     			    if ($conf->global->MAIN_MULTILANGS && empty($newlang))	$newlang = $object->thirdparty->default_lang;
     			    if (! empty($newlang)) {
     				$outputlangs = new Translate("", $conf);
@@ -810,8 +810,8 @@ if (empty($reshook))
                         // Define output language
                         $outputlangs = $langs;
                         $newlang = '';
-                        if ($conf->global->MAIN_MULTILANGS && empty($newlang) && GETPOST('lang_id'))
-                            $newlang = GETPOST('lang_id');
+                        if ($conf->global->MAIN_MULTILANGS && empty($newlang) && GETPOST('lang_id','aZ09'))
+                            $newlang = GETPOST('lang_id','aZ09');
                             if ($conf->global->MAIN_MULTILANGS && empty($newlang))
                                 $newlang = $object->thirdparty->default_lang;
                                 if (! empty($newlang)) {
diff --git a/htdocs/compta/paiement/rapport.php b/htdocs/compta/paiement/rapport.php
index a185f0aba6e..3e6427f6ac2 100644
--- a/htdocs/compta/paiement/rapport.php
+++ b/htdocs/compta/paiement/rapport.php
@@ -56,10 +56,10 @@ if ($action == 'builddoc')
     $rap = new pdf_paiement($db);
 
     $outputlangs = $langs;
-    if (GETPOST('lang_id'))
+    if (GETPOST('lang_id','aZ09'))
     {
         $outputlangs = new Translate("",$conf);
-        $outputlangs->setDefaultLang(GETPOST('lang_id'));
+        $outputlangs->setDefaultLang(GETPOST('lang_id','aZ09'));
     }
 
     // We save charset_output to restore it because write_file can change it if needed for
diff --git a/htdocs/contrat/card.php b/htdocs/contrat/card.php
index b2ab3bf3cb8..f502e8023f3 100644
--- a/htdocs/contrat/card.php
+++ b/htdocs/contrat/card.php
@@ -312,7 +312,7 @@ if (empty($reshook))
 
 										$outputlangs = $langs;
 										$newlang='';
-										if (empty($newlang) && GETPOST('lang_id')) $newlang=GETPOST('lang_id');
+										if (empty($newlang) && GETPOST('lang_id','aZ09')) $newlang=GETPOST('lang_id','aZ09');
 										if (empty($newlang)) $newlang=$srcobject->thirdparty->default_lang;
 										if (! empty($newlang))
 										{
@@ -585,7 +585,7 @@ if (empty($reshook))
 				{
 					$outputlangs = $langs;
 					$newlang = '';
-					if ($conf->global->MAIN_MULTILANGS && empty($newlang) && GETPOST('lang_id')) $newlang = GETPOST('lang_id','alpha');
+					if ($conf->global->MAIN_MULTILANGS && empty($newlang) && GETPOST('lang_id','aZ09')) $newlang = GETPOST('lang_id','aZ09');
 					if ($conf->global->MAIN_MULTILANGS && empty($newlang))	$newlang = $object->thirdparty->default_lang;
 					if (! empty($newlang)) {
 						$outputlangs = new Translate("", $conf);
@@ -922,7 +922,7 @@ if (empty($reshook))
 		$outputlangs = $langs;
 		if (! empty($conf->global->MAIN_MULTILANGS)) {
 			$outputlangs = new Translate("", $conf);
-			$newlang = (GETPOST('lang_id') ? GETPOST('lang_id') : $object->thirdparty->default_lang);
+			$newlang = (GETPOST('lang_id','aZ09') ? GETPOST('lang_id','aZ09') : $object->thirdparty->default_lang);
 			$outputlangs->setDefaultLang($newlang);
 		}
 		$ret = $object->fetch($id); // Reload to get new records
diff --git a/htdocs/core/actions_builddoc.inc.php b/htdocs/core/actions_builddoc.inc.php
index 94f4229e0db..076a7a6a035 100644
--- a/htdocs/core/actions_builddoc.inc.php
+++ b/htdocs/core/actions_builddoc.inc.php
@@ -68,7 +68,7 @@ if ($action == 'builddoc' && $permissioncreate)
         $outputlangs = $langs;
         $newlang='';
 
-        if ($conf->global->MAIN_MULTILANGS && empty($newlang) && GETPOST('lang_id')) $newlang=GETPOST('lang_id');
+        if ($conf->global->MAIN_MULTILANGS && empty($newlang) && GETPOST('lang_id','aZ09')) $newlang=GETPOST('lang_id','aZ09');
         if ($conf->global->MAIN_MULTILANGS && empty($newlang) && isset($object->thirdparty->default_lang)) $newlang=$object->thirdparty->default_lang;  // for proposal, order, invoice, ...
         if ($conf->global->MAIN_MULTILANGS && empty($newlang) && isset($object->default_lang)) $newlang=$object->default_lang;                  // for thirdparty
         if (! empty($newlang))
diff --git a/htdocs/core/actions_lineupdown.inc.php b/htdocs/core/actions_lineupdown.inc.php
index 825bdac1615..bcf251e0763 100644
--- a/htdocs/core/actions_lineupdown.inc.php
+++ b/htdocs/core/actions_lineupdown.inc.php
@@ -35,7 +35,7 @@ if ($action == 'up' && $permissiontoedit)
 	// Define output language
 	$outputlangs = $langs;
 	$newlang = '';
-	if ($conf->global->MAIN_MULTILANGS && empty($newlang) && GETPOST('lang_id')) $newlang = GETPOST('lang_id','alpha');
+	if ($conf->global->MAIN_MULTILANGS && empty($newlang) && GETPOST('lang_id','aZ09')) $newlang = GETPOST('lang_id','aZ09');
 	if ($conf->global->MAIN_MULTILANGS && empty($newlang))	$newlang = $object->thirdparty->default_lang;
 	if (! empty($newlang)) {
 		$outputlangs = new Translate("", $conf);
@@ -57,7 +57,7 @@ if ($action == 'down' && $permissiontoedit)
 	// Define output language
 	$outputlangs = $langs;
 	$newlang = '';
-	if ($conf->global->MAIN_MULTILANGS && empty($newlang) && GETPOST('lang_id')) $newlang = GETPOST('lang_id','alpha');
+	if ($conf->global->MAIN_MULTILANGS && empty($newlang) && GETPOST('lang_id','aZ09')) $newlang = GETPOST('lang_id','aZ09');
 	if ($conf->global->MAIN_MULTILANGS && empty($newlang))	$newlang = $object->thirdparty->default_lang;
 	if (! empty($newlang)) {
 		$outputlangs = new Translate("", $conf);
diff --git a/htdocs/core/actions_massactions.inc.php b/htdocs/core/actions_massactions.inc.php
index 20b3d155a27..5313b79dc04 100644
--- a/htdocs/core/actions_massactions.inc.php
+++ b/htdocs/core/actions_massactions.inc.php
@@ -400,7 +400,7 @@ if (! $error && $massaction == "builddoc" && $permtoread && ! GETPOST('button_se
     // Define output language (Here it is not used because we do only merging existing PDF)
     $outputlangs = $langs;
     $newlang='';
-    if ($conf->global->MAIN_MULTILANGS && empty($newlang) && GETPOST('lang_id')) $newlang=GETPOST('lang_id');
+    if ($conf->global->MAIN_MULTILANGS && empty($newlang) && GETPOST('lang_id','aZ09')) $newlang=GETPOST('lang_id','aZ09');
     if ($conf->global->MAIN_MULTILANGS && empty($newlang)) $newlang=$object->thirdparty->default_lang;
     if (! empty($newlang))
     {
diff --git a/htdocs/core/class/commonobject.class.php b/htdocs/core/class/commonobject.class.php
index 3c902495118..1339512b3af 100644
--- a/htdocs/core/class/commonobject.class.php
+++ b/htdocs/core/class/commonobject.class.php
@@ -3510,7 +3510,7 @@ abstract class CommonObject
 
 					$outputlangs = $langs;
 					$newlang='';
-					if (empty($newlang) && GETPOST('lang_id')) $newlang=GETPOST('lang_id');
+					if (empty($newlang) && GETPOST('lang_id','aZ09')) $newlang=GETPOST('lang_id','aZ09');
 					if (! empty($conf->global->PRODUIT_TEXTS_IN_THIRDPARTY_LANGUAGE) && empty($newlang)) $newlang=$this->thirdparty->default_lang;		// For language to language of customer
 					if (! empty($newlang))
 					{
diff --git a/htdocs/expedition/card.php b/htdocs/expedition/card.php
index b332667f681..bface3db915 100644
--- a/htdocs/expedition/card.php
+++ b/htdocs/expedition/card.php
@@ -452,7 +452,7 @@ if (empty($reshook))
 	    	{
 	    		$outputlangs = $langs;
 	    		$newlang = '';
-	    		if ($conf->global->MAIN_MULTILANGS && empty($newlang) && GETPOST('lang_id')) $newlang = GETPOST('lang_id','alpha');
+	    		if ($conf->global->MAIN_MULTILANGS && empty($newlang) && GETPOST('lang_id','aZ09')) $newlang = GETPOST('lang_id','aZ09');
 	    		if ($conf->global->MAIN_MULTILANGS && empty($newlang))	$newlang = $object->thirdparty->default_lang;
 	    		if (! empty($newlang)) {
 	    			$outputlangs = new Translate("", $conf);
@@ -549,7 +549,7 @@ if (empty($reshook))
 	    // Define output language
 	    $outputlangs = $langs;
 	    $newlang='';
-	    if ($conf->global->MAIN_MULTILANGS && empty($newlang) && GETPOST('lang_id')) $newlang=GETPOST('lang_id','alpha');
+	    if ($conf->global->MAIN_MULTILANGS && empty($newlang) && GETPOST('lang_id','aZ09')) $newlang=GETPOST('lang_id','aZ09');
 	    if ($conf->global->MAIN_MULTILANGS && empty($newlang)) $newlang=$shipment->thirdparty->default_lang;
 	    if (! empty($newlang))
 	    {
@@ -1767,7 +1767,7 @@ else if ($id || $ref)
 			$object->fetch_thirdparty();
 			$outputlangs = $langs;
 			$newlang='';
-			if (empty($newlang) && GETPOST('lang_id')) $newlang=GETPOST('lang_id','alpha');
+			if (empty($newlang) && GETPOST('lang_id','aZ09')) $newlang=GETPOST('lang_id','aZ09');
 			if (empty($newlang)) $newlang=$object->thirdparty->default_lang;
 			if (! empty($newlang))
 			{
diff --git a/htdocs/expensereport/card.php b/htdocs/expensereport/card.php
index c4aa6caccd8..e4e8fe8ea47 100644
--- a/htdocs/expensereport/card.php
+++ b/htdocs/expensereport/card.php
@@ -314,7 +314,7 @@ if (empty($reshook))
     		{
     			$outputlangs = $langs;
     			$newlang = '';
-    			if ($conf->global->MAIN_MULTILANGS && empty($newlang) && GETPOST('lang_id')) $newlang = GETPOST('lang_id','alpha');
+    			if ($conf->global->MAIN_MULTILANGS && empty($newlang) && GETPOST('lang_id','aZ09')) $newlang = GETPOST('lang_id','aZ09');
     			if ($conf->global->MAIN_MULTILANGS && empty($newlang))	$newlang = $object->thirdparty->default_lang;
     			if (! empty($newlang)) {
     				$outputlangs = new Translate("", $conf);
@@ -425,7 +425,7 @@ if (empty($reshook))
     		{
     			$outputlangs = $langs;
     			$newlang = '';
-    			if ($conf->global->MAIN_MULTILANGS && empty($newlang) && GETPOST('lang_id')) $newlang = GETPOST('lang_id','alpha');
+    			if ($conf->global->MAIN_MULTILANGS && empty($newlang) && GETPOST('lang_id','aZ09')) $newlang = GETPOST('lang_id','aZ09');
     			if ($conf->global->MAIN_MULTILANGS && empty($newlang))	$newlang = $object->thirdparty->default_lang;
     			if (! empty($newlang)) {
     				$outputlangs = new Translate("", $conf);
@@ -542,7 +542,7 @@ if (empty($reshook))
     		{
     			$outputlangs = $langs;
     			$newlang = '';
-    			if ($conf->global->MAIN_MULTILANGS && empty($newlang) && GETPOST('lang_id')) $newlang = GETPOST('lang_id','alpha');
+    			if ($conf->global->MAIN_MULTILANGS && empty($newlang) && GETPOST('lang_id','aZ09')) $newlang = GETPOST('lang_id','aZ09');
     			if ($conf->global->MAIN_MULTILANGS && empty($newlang))	$newlang = $object->thirdparty->default_lang;
     			if (! empty($newlang)) {
     				$outputlangs = new Translate("", $conf);
@@ -665,7 +665,7 @@ if (empty($reshook))
     		{
     			$outputlangs = $langs;
     			$newlang = '';
-    			if ($conf->global->MAIN_MULTILANGS && empty($newlang) && GETPOST('lang_id')) $newlang = GETPOST('lang_id','alpha');
+    			if ($conf->global->MAIN_MULTILANGS && empty($newlang) && GETPOST('lang_id','aZ09')) $newlang = GETPOST('lang_id','aZ09');
     			if ($conf->global->MAIN_MULTILANGS && empty($newlang))	$newlang = $object->thirdparty->default_lang;
     			if (! empty($newlang)) {
     				$outputlangs = new Translate("", $conf);
@@ -788,7 +788,7 @@ if (empty($reshook))
     			{
     				$outputlangs = $langs;
     				$newlang = '';
-    				if ($conf->global->MAIN_MULTILANGS && empty($newlang) && GETPOST('lang_id')) $newlang = GETPOST('lang_id','alpha');
+    				if ($conf->global->MAIN_MULTILANGS && empty($newlang) && GETPOST('lang_id','aZ09')) $newlang = GETPOST('lang_id','aZ09');
     				if ($conf->global->MAIN_MULTILANGS && empty($newlang))	$newlang = $object->thirdparty->default_lang;
     				if (! empty($newlang)) {
     					$outputlangs = new Translate("", $conf);
@@ -910,7 +910,7 @@ if (empty($reshook))
     			{
     				$outputlangs = $langs;
     				$newlang = '';
-    				if ($conf->global->MAIN_MULTILANGS && empty($newlang) && GETPOST('lang_id')) $newlang = GETPOST('lang_id','alpha');
+    				if ($conf->global->MAIN_MULTILANGS && empty($newlang) && GETPOST('lang_id','aZ09')) $newlang = GETPOST('lang_id','aZ09');
     				if ($conf->global->MAIN_MULTILANGS && empty($newlang))	$newlang = $object->thirdparty->default_lang;
     				if (! empty($newlang)) {
     					$outputlangs = new Translate("", $conf);
@@ -953,7 +953,7 @@ if (empty($reshook))
     		{
     			$outputlangs = $langs;
     			$newlang = '';
-    			if ($conf->global->MAIN_MULTILANGS && empty($newlang) && GETPOST('lang_id')) $newlang = GETPOST('lang_id','alpha');
+    			if ($conf->global->MAIN_MULTILANGS && empty($newlang) && GETPOST('lang_id','aZ09')) $newlang = GETPOST('lang_id','aZ09');
     			if ($conf->global->MAIN_MULTILANGS && empty($newlang))	$newlang = $object->thirdparty->default_lang;
     			if (! empty($newlang)) {
     				$outputlangs = new Translate("", $conf);
@@ -1170,7 +1170,7 @@ if (empty($reshook))
     			{
     				$outputlangs = $langs;
     				$newlang = '';
-    				if ($conf->global->MAIN_MULTILANGS && empty($newlang) && GETPOST('lang_id')) $newlang = GETPOST('lang_id','alpha');
+    				if ($conf->global->MAIN_MULTILANGS && empty($newlang) && GETPOST('lang_id','aZ09')) $newlang = GETPOST('lang_id','aZ09');
     				if ($conf->global->MAIN_MULTILANGS && empty($newlang))	$newlang = $object->thirdparty->default_lang;
     				if (! empty($newlang)) {
     					$outputlangs = new Translate("", $conf);
@@ -1236,7 +1236,7 @@ if (empty($reshook))
     				{
     					$outputlangs = $langs;
     					$newlang = '';
-    					if ($conf->global->MAIN_MULTILANGS && empty($newlang) && GETPOST('lang_id')) $newlang = GETPOST('lang_id','alpha');
+    					if ($conf->global->MAIN_MULTILANGS && empty($newlang) && GETPOST('lang_id','aZ09')) $newlang = GETPOST('lang_id','aZ09');
     					if ($conf->global->MAIN_MULTILANGS && empty($newlang))	$newlang = $object->thirdparty->default_lang;
     					if (! empty($newlang)) {
     						$outputlangs = new Translate("", $conf);
diff --git a/htdocs/fichinter/card.php b/htdocs/fichinter/card.php
index 272a15e6ab8..953b48a8adf 100644
--- a/htdocs/fichinter/card.php
+++ b/htdocs/fichinter/card.php
@@ -150,7 +150,7 @@ if (empty($reshook))
 				// Define output language
 				$outputlangs = $langs;
 				$newlang='';
-				if ($conf->global->MAIN_MULTILANGS && empty($newlang) && GETPOST('lang_id','alpha')) $newlang=GETPOST('lang_id','alpha');
+				if ($conf->global->MAIN_MULTILANGS && empty($newlang) && GETPOST('lang_id','aZ09')) $newlang=GETPOST('lang_id','aZ09');
 				if ($conf->global->MAIN_MULTILANGS && empty($newlang)) $newlang=$object->thirdparty->default_lang;
 				if (! empty($newlang))
 				{
@@ -179,7 +179,7 @@ if (empty($reshook))
 				// Define output language
 				$outputlangs = $langs;
 				$newlang='';
-				if ($conf->global->MAIN_MULTILANGS && empty($newlang) && GETPOST('lang_id','alpha')) $newlang=GETPOST('lang_id','alpha');
+				if ($conf->global->MAIN_MULTILANGS && empty($newlang) && GETPOST('lang_id','aZ09')) $newlang=GETPOST('lang_id','aZ09');
 				if ($conf->global->MAIN_MULTILANGS && empty($newlang)) $newlang=$object->thirdparty->default_lang;
 				if (! empty($newlang))
 				{
@@ -296,7 +296,7 @@ if (empty($reshook))
 										$prod->fetch($lines[$i]->fk_product);
 										$outputlangs = $langs;
 										$newlang='';
-										if (empty($newlang) && GETPOST('lang_id')) $newlang=GETPOST('lang_id');
+										if (empty($newlang) && GETPOST('lang_id','aZ09')) $newlang=GETPOST('lang_id','aZ09');
 										if (empty($newlang)) $newlang=$srcobject->client->default_lang;
 										if (! empty($newlang)) {
 											$outputlangs = new Translate("",$conf);
@@ -513,7 +513,7 @@ if (empty($reshook))
 			// Define output language
 			$outputlangs = $langs;
 			$newlang='';
-			if ($conf->global->MAIN_MULTILANGS && empty($newlang) && GETPOST('lang_id','alpha')) $newlang=GETPOST('lang_id','alpha');
+			if ($conf->global->MAIN_MULTILANGS && empty($newlang) && GETPOST('lang_id','aZ09')) $newlang=GETPOST('lang_id','aZ09');
 			if ($conf->global->MAIN_MULTILANGS && empty($newlang)) $newlang=$object->thirdparty->default_lang;
 			if (! empty($newlang))
 			{
@@ -625,7 +625,7 @@ if (empty($reshook))
 		// Define output language
 		$outputlangs = $langs;
 		$newlang='';
-		if ($conf->global->MAIN_MULTILANGS && empty($newlang) && GETPOST('lang_id','alpha')) $newlang=GETPOST('lang_id','alpha');
+		if ($conf->global->MAIN_MULTILANGS && empty($newlang) && GETPOST('lang_id','aZ09')) $newlang=GETPOST('lang_id','aZ09');
 		if ($conf->global->MAIN_MULTILANGS && empty($newlang)) $newlang=$object->thirdparty->default_lang;
 		if (! empty($newlang))
 		{
@@ -660,7 +660,7 @@ if (empty($reshook))
 		// Define output language
 		$outputlangs = $langs;
 		$newlang='';
-		if ($conf->global->MAIN_MULTILANGS && empty($newlang) && GETPOST('lang_id','alpha')) $newlang=GETPOST('lang_id','alpha');
+		if ($conf->global->MAIN_MULTILANGS && empty($newlang) && GETPOST('lang_id','aZ09')) $newlang=GETPOST('lang_id','aZ09');
 		if ($conf->global->MAIN_MULTILANGS && empty($newlang)) $newlang=$object->thirdparty->default_lang;
 		if (! empty($newlang))
 		{
@@ -681,7 +681,7 @@ if (empty($reshook))
 		// Define output language
 		$outputlangs = $langs;
 		$newlang='';
-		if ($conf->global->MAIN_MULTILANGS && empty($newlang) && GETPOST('lang_id','alpha')) $newlang=GETPOST('lang_id','alpha');
+		if ($conf->global->MAIN_MULTILANGS && empty($newlang) && GETPOST('lang_id','aZ09')) $newlang=GETPOST('lang_id','aZ09');
 		if ($conf->global->MAIN_MULTILANGS && empty($newlang)) $newlang=$object->thirdparty->default_lang;
 		if (! empty($newlang))
 		{
@@ -701,7 +701,7 @@ if (empty($reshook))
 		// Define output language
 		$outputlangs = $langs;
 		$newlang='';
-		if ($conf->global->MAIN_MULTILANGS && empty($newlang) && GETPOST('lang_id','alpha')) $newlang=GETPOST('lang_id','alpha');
+		if ($conf->global->MAIN_MULTILANGS && empty($newlang) && GETPOST('lang_id','aZ09')) $newlang=GETPOST('lang_id','aZ09');
 		if ($conf->global->MAIN_MULTILANGS && empty($newlang)) $newlang=$object->thirdparty->default_lang;
 		if (! empty($newlang))
 		{
diff --git a/htdocs/fourn/commande/card.php b/htdocs/fourn/commande/card.php
index c76a25caa70..bdd38ebc0b7 100644
--- a/htdocs/fourn/commande/card.php
+++ b/htdocs/fourn/commande/card.php
@@ -477,7 +477,7 @@ if (empty($reshook))
 	    	{
 	    		$outputlangs = $langs;
 	    		$newlang = '';
-	    		if ($conf->global->MAIN_MULTILANGS && empty($newlang) && GETPOST('lang_id')) $newlang = GETPOST('lang_id','alpha');
+	    		if ($conf->global->MAIN_MULTILANGS && empty($newlang) && GETPOST('lang_id','aZ09')) $newlang = GETPOST('lang_id','aZ09');
 	    		if ($conf->global->MAIN_MULTILANGS && empty($newlang))	$newlang = $object->thirdparty->default_lang;
 	    		if (! empty($newlang)) {
 	    			$outputlangs = new Translate("", $conf);
@@ -628,7 +628,7 @@ if (empty($reshook))
 	    	{
 	    		$outputlangs = $langs;
 	    		$newlang = '';
-	    		if ($conf->global->MAIN_MULTILANGS && empty($newlang) && GETPOST('lang_id')) $newlang = GETPOST('lang_id','alpha');
+	    		if ($conf->global->MAIN_MULTILANGS && empty($newlang) && GETPOST('lang_id','aZ09')) $newlang = GETPOST('lang_id','aZ09');
 	    		if ($conf->global->MAIN_MULTILANGS && empty($newlang))	$newlang = $object->thirdparty->default_lang;
 	    		if (! empty($newlang)) {
 	    			$outputlangs = new Translate("", $conf);
@@ -657,8 +657,8 @@ if (empty($reshook))
 			// Define output language
 			$outputlangs = $langs;
 			$newlang = '';
-			if ($conf->global->MAIN_MULTILANGS && empty($newlang) && GETPOST('lang_id'))
-				$newlang = GETPOST('lang_id');
+			if ($conf->global->MAIN_MULTILANGS && empty($newlang) && GETPOST('lang_id','aZ09'))
+				$newlang = GETPOST('lang_id','aZ09');
 			if ($conf->global->MAIN_MULTILANGS && empty($newlang))
 				$newlang = $object->thirdparty->default_lang;
 			if (! empty($newlang)) {
@@ -696,7 +696,7 @@ if (empty($reshook))
 	    	{
 	    		$outputlangs = $langs;
 	    		$newlang = '';
-	    		if ($conf->global->MAIN_MULTILANGS && empty($newlang) && GETPOST('lang_id')) $newlang = GETPOST('lang_id','alpha');
+	    		if ($conf->global->MAIN_MULTILANGS && empty($newlang) && GETPOST('lang_id','aZ09')) $newlang = GETPOST('lang_id','aZ09');
 	    		if ($conf->global->MAIN_MULTILANGS && empty($newlang))	$newlang = $object->thirdparty->default_lang;
 	    		if (! empty($newlang)) {
 	    			$outputlangs = new Translate("", $conf);
@@ -754,7 +754,7 @@ if (empty($reshook))
 	            if (empty($conf->global->MAIN_DISABLE_PDF_AUTOUPDATE)) {
 	                $outputlangs = $langs;
 	                $newlang = '';
-	                if ($conf->global->MAIN_MULTILANGS && empty($newlang) && GETPOST('lang_id')) $newlang = GETPOST('lang_id','alpha');
+	                if ($conf->global->MAIN_MULTILANGS && empty($newlang) && GETPOST('lang_id','aZ09')) $newlang = GETPOST('lang_id','aZ09');
 	                if ($conf->global->MAIN_MULTILANGS && empty($newlang))	$newlang = $object->thirdparty->default_lang;
 	                if (! empty($newlang)) {
 	                    $outputlangs = new Translate("", $conf);
@@ -795,7 +795,7 @@ if (empty($reshook))
 	        {
 	            $outputlangs = $langs;
 	            $newlang = '';
-	            if ($conf->global->MAIN_MULTILANGS && empty($newlang) && GETPOST('lang_id')) $newlang = GETPOST('lang_id','alpha');
+	            if ($conf->global->MAIN_MULTILANGS && empty($newlang) && GETPOST('lang_id','aZ09')) $newlang = GETPOST('lang_id','aZ09');
 	            if ($conf->global->MAIN_MULTILANGS && empty($newlang))	$newlang = $object->thirdparty->default_lang;
 	            if (! empty($newlang)) {
 	                $outputlangs = new Translate("", $conf);
diff --git a/htdocs/fourn/facture/card.php b/htdocs/fourn/facture/card.php
index 956808b1fab..f0a0985a82c 100644
--- a/htdocs/fourn/facture/card.php
+++ b/htdocs/fourn/facture/card.php
@@ -198,7 +198,7 @@ if (empty($reshook))
 	            {
                     $outputlangs = $langs;
                     $newlang = '';
-                    if ($conf->global->MAIN_MULTILANGS && empty($newlang) && GETPOST('lang_id')) $newlang = GETPOST('lang_id','alpha');
+                    if ($conf->global->MAIN_MULTILANGS && empty($newlang) && GETPOST('lang_id','aZ09')) $newlang = GETPOST('lang_id','aZ09');
                     if ($conf->global->MAIN_MULTILANGS && empty($newlang))	$newlang = $object->thirdparty->default_lang;
                     if (! empty($newlang)) {
                         $outputlangs = new Translate("", $conf);
@@ -239,8 +239,8 @@ if (empty($reshook))
 			// Define output language
 			/*$outputlangs = $langs;
 			$newlang = '';
-			if ($conf->global->MAIN_MULTILANGS && empty($newlang) && GETPOST('lang_id'))
-				$newlang = GETPOST('lang_id');
+			if ($conf->global->MAIN_MULTILANGS && empty($newlang) && GETPOST('lang_id','aZ09'))
+				$newlang = GETPOST('lang_id','aZ09');
 			if ($conf->global->MAIN_MULTILANGS && empty($newlang))
 				$newlang = $object->thirdparty->default_lang;
 			if (! empty($newlang)) {
@@ -286,8 +286,8 @@ if (empty($reshook))
 		    // Define output language
 		    $outputlangs = $langs;
 		    $newlang = '';
-		    if ($conf->global->MAIN_MULTILANGS && empty($newlang) && GETPOST('lang_id'))
-		        $newlang = GETPOST('lang_id');
+		    if ($conf->global->MAIN_MULTILANGS && empty($newlang) && GETPOST('lang_id','aZ09'))
+		        $newlang = GETPOST('lang_id','aZ09');
 		        if ($conf->global->MAIN_MULTILANGS && empty($newlang))
 		            $newlang = $object->thirdparty->default_lang;
 		            if (! empty($newlang)) {
@@ -1064,7 +1064,7 @@ if (empty($reshook))
 	    	{
 	    		$outputlangs = $langs;
 	    		$newlang = '';
-	    		if ($conf->global->MAIN_MULTILANGS && empty($newlang) && GETPOST('lang_id')) $newlang = GETPOST('lang_id','alpha');
+	    		if ($conf->global->MAIN_MULTILANGS && empty($newlang) && GETPOST('lang_id','aZ09')) $newlang = GETPOST('lang_id','aZ09');
 	    		if ($conf->global->MAIN_MULTILANGS && empty($newlang))	$newlang = $object->thirdparty->default_lang;
 	    		if (! empty($newlang)) {
 	    			$outputlangs = new Translate("", $conf);
@@ -1146,7 +1146,7 @@ if (empty($reshook))
 	    	{
 	    		$outputlangs = $langs;
 	    		$newlang = '';
-	    		if ($conf->global->MAIN_MULTILANGS && empty($newlang) && GETPOST('lang_id')) $newlang = GETPOST('lang_id','alpha');
+	    		if ($conf->global->MAIN_MULTILANGS && empty($newlang) && GETPOST('lang_id','aZ09')) $newlang = GETPOST('lang_id','aZ09');
 	    		if ($conf->global->MAIN_MULTILANGS && empty($newlang))	$newlang = $object->thirdparty->default_lang;
 	    		if (! empty($newlang)) {
 	    			$outputlangs = new Translate("", $conf);
diff --git a/htdocs/fourn/facture/rapport.php b/htdocs/fourn/facture/rapport.php
index f2bb499d652..d0a0c5f0aea 100644
--- a/htdocs/fourn/facture/rapport.php
+++ b/htdocs/fourn/facture/rapport.php
@@ -56,10 +56,10 @@ if ($action == 'builddoc')
     $rap = new pdf_paiement_fourn($db);
 
     $outputlangs = $langs;
-    if (GETPOST('lang_id'))
+    if (GETPOST('lang_id','aZ09'))
     {
         $outputlangs = new Translate("",$conf);
-        $outputlangs->setDefaultLang(GETPOST('lang_id'));
+        $outputlangs->setDefaultLang(GETPOST('lang_id','aZ09'));
     }
 
     // We save charset_output to restore it because write_file can change it if needed for
diff --git a/htdocs/fourn/paiement/card.php b/htdocs/fourn/paiement/card.php
index 40037dce274..ee32ddcfb05 100644
--- a/htdocs/fourn/paiement/card.php
+++ b/htdocs/fourn/paiement/card.php
@@ -150,7 +150,7 @@ if ($action == 'builddoc')
 	if (GETPOST('model')) $object->setDocModel($user, GETPOST('model','alpha'));
 
     $outputlangs = $langs;
-    $newlang=GETPOST('lang_id','alpha');
+    $newlang=GETPOST('lang_id','aZ09');
     if ($conf->global->MAIN_MULTILANGS && empty($newlang)) $newlang=$object->thirdparty->default_lang;
     if (! empty($newlang))
     {
diff --git a/htdocs/livraison/card.php b/htdocs/livraison/card.php
index bf8dc3e9bed..02b126306f2 100644
--- a/htdocs/livraison/card.php
+++ b/htdocs/livraison/card.php
@@ -142,7 +142,7 @@ else if ($action == 'confirm_valid' && $confirm == 'yes' &&
 	{
 		$outputlangs = $langs;
 		$newlang = '';
-		if ($conf->global->MAIN_MULTILANGS && empty($newlang) && GETPOST('lang_id')) $newlang = GETPOST('lang_id','alpha');
+		if ($conf->global->MAIN_MULTILANGS && empty($newlang) && GETPOST('lang_id','aZ09')) $newlang = GETPOST('lang_id','aZ09');
 		if ($conf->global->MAIN_MULTILANGS && empty($newlang))	$newlang = $object->thirdparty->default_lang;
 		if (! empty($newlang)) {
 			$outputlangs = new Translate("", $conf);
@@ -259,7 +259,7 @@ if ($action == 'builddoc')	// En get ou en post
 	// Define output language
 	$outputlangs = $langs;
 	$newlang='';
-	if ($conf->global->MAIN_MULTILANGS && empty($newlang) && GETPOST('lang_id')) $newlang=GETPOST('lang_id');
+	if ($conf->global->MAIN_MULTILANGS && empty($newlang) && GETPOST('lang_id','aZ09')) $newlang=GETPOST('lang_id','aZ09');
 	if ($conf->global->MAIN_MULTILANGS && empty($newlang)) $newlang=$object->thirdparty->default_lang;
 	if (! empty($newlang))
 	{
diff --git a/htdocs/product/document.php b/htdocs/product/document.php
index 72a76ea2448..53bbbfeeabb 100644
--- a/htdocs/product/document.php
+++ b/htdocs/product/document.php
@@ -125,7 +125,7 @@ if ($action=='filemerge')
 		$filetomerge_file_array = GETPOST('filetoadd');
 
 		if ($conf->global->MAIN_MULTILANGS) {
-			$lang_id = GETPOST('lang_id');
+			$lang_id = GETPOST('lang_id','aZ09');
 		}
 
 		// Delete all file already associated
@@ -245,7 +245,7 @@ if ($object->id)
     	$filetomerge = new Propalmergepdfproduct($db);
 
     	if ($conf->global->MAIN_MULTILANGS) {
-    		$lang_id = GETPOST('lang_id');
+    		$lang_id = GETPOST('lang_id','aZ09');
     		$result = $filetomerge->fetch_by_product($object->id, $lang_id);
     	} else {
     		$result = $filetomerge->fetch_by_product($object->id);
diff --git a/htdocs/projet/card.php b/htdocs/projet/card.php
index 7b0b448ef59..b8528e9863c 100644
--- a/htdocs/projet/card.php
+++ b/htdocs/projet/card.php
@@ -339,10 +339,10 @@ if (empty($reshook))
 		if (GETPOST('model')) $object->setDocModel($user, GETPOST('model','alpha'));
 
 	    $outputlangs = $langs;
-	    if (GETPOST('lang_id'))
+	    if (GETPOST('lang_id','aZ09'))
 	    {
 	        $outputlangs = new Translate("",$conf);
-	        $outputlangs->setDefaultLang(GETPOST('lang_id'));
+	        $outputlangs->setDefaultLang(GETPOST('lang_id','aZ09'));
 	    }
 	    $result= $object->generateDocument($object->modelpdf, $outputlangs);
 	    if ($result <= 0)
diff --git a/htdocs/projet/tasks/task.php b/htdocs/projet/tasks/task.php
index df89cac3e83..f85b5071de1 100644
--- a/htdocs/projet/tasks/task.php
+++ b/htdocs/projet/tasks/task.php
@@ -162,10 +162,10 @@ if ($action == 'builddoc' && $user->rights->projet->creer)
 	if (GETPOST('model')) $object->setDocModel($user, GETPOST('model','alpha'));
 
 	$outputlangs = $langs;
-	if (GETPOST('lang_id'))
+	if (GETPOST('lang_id','aZ09'))
 	{
 		$outputlangs = new Translate("",$conf);
-		$outputlangs->setDefaultLang(GETPOST('lang_id'));
+		$outputlangs->setDefaultLang(GETPOST('lang_id','aZ09'));
 	}
 	$result= $object->generateDocument($object->modelpdf, $outputlangs);
 	if ($result <= 0)
diff --git a/htdocs/societe/canvas/actions_card_common.class.php b/htdocs/societe/canvas/actions_card_common.class.php
index 689771ad223..452a9cc6a61 100644
--- a/htdocs/societe/canvas/actions_card_common.class.php
+++ b/htdocs/societe/canvas/actions_card_common.class.php
@@ -335,7 +335,7 @@ abstract class ActionsCardCommon
                 // Define output language
                 $outputlangs = $langs;
                 $newlang='';
-                if ($conf->global->MAIN_MULTILANGS && empty($newlang) && GETPOST('lang_id')) $newlang=GETPOST('lang_id');
+                if ($conf->global->MAIN_MULTILANGS && empty($newlang) && GETPOST('lang_id','aZ09')) $newlang=GETPOST('lang_id','aZ09');
                 if ($conf->global->MAIN_MULTILANGS && empty($newlang)) $newlang=$this->object->default_lang;
                 if (! empty($newlang))
                 {
diff --git a/htdocs/societe/consumption.php b/htdocs/societe/consumption.php
index 834131a86a8..d11a358f56c 100644
--- a/htdocs/societe/consumption.php
+++ b/htdocs/societe/consumption.php
@@ -457,7 +457,7 @@ if ($sql_select)
 
 				$outputlangs = $langs;
 				$newlang='';
-				if (empty($newlang) && GETPOST('lang_id')) $newlang=GETPOST('lang_id');
+				if (empty($newlang) && GETPOST('lang_id','aZ09')) $newlang=GETPOST('lang_id','aZ09');
 				if (empty($newlang)) $newlang=$object->default_lang;
 				if (! empty($newlang))
 				{
diff --git a/htdocs/supplier_proposal/card.php b/htdocs/supplier_proposal/card.php
index b4d93feb511..e5040b3150d 100644
--- a/htdocs/supplier_proposal/card.php
+++ b/htdocs/supplier_proposal/card.php
@@ -173,7 +173,7 @@ if (empty($reshook))
 			$outputlangs = $langs;
 			if (! empty($conf->global->MAIN_MULTILANGS)) {
 				$outputlangs = new Translate("", $conf);
-				$newlang = (GETPOST('lang_id') ? GETPOST('lang_id') : $object->thirdparty->default_lang);
+				$newlang = (GETPOST('lang_id','aZ09') ? GETPOST('lang_id','aZ09') : $object->thirdparty->default_lang);
 				$outputlangs->setDefaultLang($newlang);
 			}
 			$ret = $object->fetch($id); // Reload to get new records
@@ -200,7 +200,7 @@ if (empty($reshook))
 				{
 					$outputlangs = $langs;
 					$newlang = '';
-					if ($conf->global->MAIN_MULTILANGS && empty($newlang) && GETPOST('lang_id')) $newlang = GETPOST('lang_id','alpha');
+					if ($conf->global->MAIN_MULTILANGS && empty($newlang) && GETPOST('lang_id','aZ09')) $newlang = GETPOST('lang_id','aZ09');
 					if ($conf->global->MAIN_MULTILANGS && empty($newlang))	$newlang = $object->thirdparty->default_lang;
 					if (! empty($newlang)) {
 						$outputlangs = new Translate("", $conf);
@@ -401,7 +401,7 @@ if (empty($reshook))
 				    	{
 				    		$outputlangs = $langs;
 				    		$newlang = '';
-				    		if ($conf->global->MAIN_MULTILANGS && empty($newlang) && GETPOST('lang_id')) $newlang = GETPOST('lang_id','alpha');
+				    		if ($conf->global->MAIN_MULTILANGS && empty($newlang) && GETPOST('lang_id','aZ09')) $newlang = GETPOST('lang_id','aZ09');
 				    		if ($conf->global->MAIN_MULTILANGS && empty($newlang))	$newlang = $object->thirdparty->default_lang;
 				    		if (! empty($newlang)) {
 				    			$outputlangs = new Translate("", $conf);
@@ -485,7 +485,7 @@ if (empty($reshook))
 			$outputlangs = $langs;
 			if (! empty($conf->global->MAIN_MULTILANGS)) {
 				$outputlangs = new Translate("", $conf);
-				$newlang = (GETPOST('lang_id') ? GETPOST('lang_id') : $object->thirdparty->default_lang);
+				$newlang = (GETPOST('lang_id','aZ09') ? GETPOST('lang_id','aZ09') : $object->thirdparty->default_lang);
 				$outputlangs->setDefaultLang($newlang);
 			}
 			$ret = $object->fetch($id); // Reload to get new records
@@ -693,7 +693,7 @@ if (empty($reshook))
 					{
 						$outputlangs = $langs;
 						$newlang = '';
-			    		if ($conf->global->MAIN_MULTILANGS && empty($newlang) && GETPOST('lang_id')) $newlang = GETPOST('lang_id','alpha');
+			    		if ($conf->global->MAIN_MULTILANGS && empty($newlang) && GETPOST('lang_id','aZ09')) $newlang = GETPOST('lang_id','aZ09');
 	    				if ($conf->global->MAIN_MULTILANGS && empty($newlang))	$newlang = $object->thirdparty->default_lang;
 	    				if (! empty($newlang)) {
 							$outputlangs = new Translate("", $conf);
@@ -828,7 +828,7 @@ if (empty($reshook))
 					$outputlangs = $langs;
 					if (! empty($conf->global->MAIN_MULTILANGS)) {
 						$outputlangs = new Translate("", $conf);
-						$newlang = (GETPOST('lang_id') ? GETPOST('lang_id') : $object->thirdparty->default_lang);
+						$newlang = (GETPOST('lang_id','aZ09') ? GETPOST('lang_id','aZ09') : $object->thirdparty->default_lang);
 						$outputlangs->setDefaultLang($newlang);
 					}
 					$ret = $object->fetch($id); // Reload to get new records
@@ -884,7 +884,7 @@ if (empty($reshook))
 		$outputlangs = $langs;
 		if (! empty($conf->global->MAIN_MULTILANGS)) {
 			$outputlangs = new Translate("", $conf);
-			$newlang = (GETPOST('lang_id') ? GETPOST('lang_id') : $object->thirdparty->default_lang);
+			$newlang = (GETPOST('lang_id','aZ09') ? GETPOST('lang_id','aZ09') : $object->thirdparty->default_lang);
 			$outputlangs->setDefaultLang($newlang);
 		}
 		$ret = $object->fetch($id); // Reload to get new records
diff --git a/htdocs/supplier_proposal/class/supplier_proposal.class.php b/htdocs/supplier_proposal/class/supplier_proposal.class.php
index b14e4a40ff9..bf0d42b889a 100644
--- a/htdocs/supplier_proposal/class/supplier_proposal.class.php
+++ b/htdocs/supplier_proposal/class/supplier_proposal.class.php
@@ -1661,7 +1661,7 @@ class SupplierProposal extends CommonObject
                	if (! empty($conf->global->MAIN_MULTILANGS))
                	{
                		$outputlangs = new Translate("",$conf);
-               		$newlang=(GETPOST('lang_id') ? GETPOST('lang_id') : $this->thirdparty->default_lang);
+               		$newlang=(GETPOST('lang_id','aZ09') ? GETPOST('lang_id','aZ09') : $this->thirdparty->default_lang);
                		$outputlangs->setDefaultLang($newlang);
                	}
                	//$ret=$object->fetch($id);    // Reload to get new records