diff --git a/htdocs/install/etape5.php b/htdocs/install/etape5.php
index f884b6a1391..dc145c5da14 100644
--- a/htdocs/install/etape5.php
+++ b/htdocs/install/etape5.php
@@ -174,8 +174,9 @@ if ($_POST["action"] == "set" || $_POST["action"] == "upgrade")
     	}
     }
 
-    $db->query("UPDATE llx_const set value='".$setuplang."' WHERE name='MAIN_LANG_DEFAULT';");
-            
+    // May fail if parameter already defined
+    $resql=$db->query("INSERT INTO llx_const(name,value,type,visible,note) values('MAIN_LANG_DEFAULT','".$setuplang."','chaine',0,'Default language')");
+	
     print '</table>';
 
     $db->close();
diff --git a/mysql/data/data.sql b/mysql/data/data.sql
index 07c6c029b8f..7ba08c4b917 100644
--- a/mysql/data/data.sql
+++ b/mysql/data/data.sql
@@ -74,7 +74,7 @@ insert into llx_const(name,value,type,visible,note) values('MAIN_FASTSEARCH_PROD
 --
 -- IHM
 --
-insert into llx_const (name, value, type, note, visible) values ('MAIN_LANG_DEFAULT','fr_FR','chaine','Langue par défaut pour les écrans Dolibarr',0);
+
 insert into llx_const (name, value, type, note, visible) values ('MAIN_SIZE_LISTE_LIMIT','25','chaine','Longueur maximum des listes',0);
 insert into llx_const (name, value, type, note, visible) values ('MAIN_SHOW_WORKBOARD','1','yesno','Affichage tableau de bord de travail Dolibarr',0);