diff --git a/htdocs/admin/ihm.php b/htdocs/admin/ihm.php
index 10f3d009b13..27c86bbae0d 100644
--- a/htdocs/admin/ihm.php
+++ b/htdocs/admin/ihm.php
@@ -244,6 +244,11 @@ else
     print '<tr '.$bc[$var].'"><td width="35%">'.$langs->trans("DisableJavascript").'</td><td>';   
     print yn($conf->global->MAIN_DISABLE_JAVASCRIPT)."</td></tr>";
     
+    // Disable ajax
+    $var=!$var;
+    print '<tr '.$bc[$var].'"><td width="35%">'.$langs->trans("DisableAjax").'</td><td>';   
+    print yn($conf->global->MAIN_DISABLE_AJAX)."</td></tr>";
+    
     // Calendrier en popup
     $var=!$var;
     print '<tr '.$bc[$var].'"><td width="35%">'.$langs->trans("UsePopupCalendar").'</td><td>';   
diff --git a/htdocs/html.form.class.php b/htdocs/html.form.class.php
index 62bd6d7a167..781191c0490 100644
--- a/htdocs/html.form.class.php
+++ b/htdocs/html.form.class.php
@@ -615,7 +615,7 @@ class Form
     function select_produits($selected='',$htmlname='productid',$filtretype='',$limit=20,$price_level=0)
     {
 		global $langs,$conf,$user;
-		if($regis=="je_te_laisse_faire_la_modif")
+		if($conf->use_ajax)
 		{
 		?>
 		<script type="text/javascript" src="<?=DOL_URL_ROOT?>/lib/prototype.js"></script>
diff --git a/htdocs/master.inc.php b/htdocs/master.inc.php
index 4022c5e0887..b10e8895f81 100644
--- a/htdocs/master.inc.php
+++ b/htdocs/master.inc.php
@@ -362,6 +362,10 @@ if (isset($conf->global->MAIN_USE_PREVIEW_TABS)) $conf->use_preview_tabs=$conf->
 $conf->use_javascript=1;
 if (isset($conf->global->MAIN_DISABLE_JAVASCRIPT)) $conf->use_javascript=! $conf->global->MAIN_DISABLE_JAVASCRIPT;
 
+// conf->use_ajax
+$conf->use_ajax=""; // Pas d' Ajax par defaut
+if (isset($conf->global->MAIN_DISABLE_AJAX)) $conf->use_ajax=! $conf->global->MAIN_DISABLE_AJAX;
+
 // conf->use_popup_calendar
 $conf->use_popup_calendar="";	// Pas de date popup par defaut
 if (isset($conf->global->MAIN_POPUP_CALENDAR)) $conf->use_popup_calendar=$conf->global->MAIN_POPUP_CALENDAR;