diff --git a/htdocs/about.php b/htdocs/about.php
index b77895543432b00f09f9c06698c58ba8f79c3a21..590431fcf5b835f856c4764e46d0096b80d61e99 100644
--- a/htdocs/about.php
+++ b/htdocs/about.php
@@ -81,7 +81,7 @@ print '</ul>';
 
 
 // \todo Faut-il inviter l'utilisateur � aller sur le site en fran�ais si sa langue n'est pas le fran�ais ?
-//if (eregi('^fr_',$conf->langage)
+//if (eregi('^fr_',$langs->getDefaultLang())
 //{
     print '<p>';
     print 'Vente / Support';
diff --git a/htdocs/admin/system/dolibarr.php b/htdocs/admin/system/dolibarr.php
index dbec3def1c6abe64b8ea724b01abd37dea1bebb7..00cb21cebc10ba34c073b5f67c1874a428368029 100644
--- a/htdocs/admin/system/dolibarr.php
+++ b/htdocs/admin/system/dolibarr.php
@@ -44,12 +44,21 @@ print "<tr $bc[0]><td width=\"240\">".$langs->trans("Version")."</td><td>".DOL_V
 print '</table>';
 print '<br>';
 
+$var=true;
 print '<table class="noborder" width="100%">';
-print '<tr class="liste_titre"><td>'.$langs->trans("Parameter").'</td><td>'.$langs->trans("Value").'</td></tr>'."\n";
-print "<tr $bc[0]><td width=\"240\">".$langs->trans("Language")." (LC_ALL)</td><td>".setlocale(LC_ALL,0)."</td></tr>\n";
-print "<tr $bc[1]><td width=\"240\">".$langs->trans("Language")." (LC_NUMERIC)</td><td>".setlocale(LC_NUMERIC,0)."</td></tr>\n";
-print "<tr $bc[0]><td width=\"240\">".$langs->trans("Language")." (LC_TIME)</td><td>".setlocale(LC_TIME,0)."</td></tr>\n";
-print "<tr $bc[1]><td width=\"240\">".$langs->trans("Language")." (LC_MONETARY)</td><td>".setlocale(LC_MONETARY,0)."</td></tr>\n";
+print '<tr class="liste_titre"><td>'.$langs->trans("LanguageDolibarrParameter").'</td><td>'.$langs->trans("Value").'</td></tr>'."\n";
+$var=!$var;
+print "<tr ".$bc[$var]."><td width=\"240\">".$langs->trans("LanguageBrowserParameter","HTTP_ACCEPT_LANGUAGE")."</td><td>".$_SERVER["HTTP_ACCEPT_LANGUAGE"]."</td></tr>\n";
+$var=!$var;
+print "<tr ".$bc[$var]."><td width=\"240\">".$langs->trans("LanguageParameter","PHP LC_ALL")."</td><td>".setlocale(LC_ALL,0)."</td></tr>\n";
+$var=!$var;
+print "<tr ".$bc[$var]."><td width=\"240\">".$langs->trans("LanguageParameter","PHP LC_NUMERIC")."</td><td>".setlocale(LC_NUMERIC,0)."</td></tr>\n";
+$var=!$var;
+print "<tr ".$bc[$var]."><td width=\"240\">".$langs->trans("LanguageParameter","PHP LC_TIME")."</td><td>".setlocale(LC_TIME,0)."</td></tr>\n";
+$var=!$var;
+print "<tr ".$bc[$var]."><td width=\"240\">".$langs->trans("LanguageParameter","PHP LC_MONETARY")."</td><td>".setlocale(LC_MONETARY,0)."</td></tr>\n";
+$var=!$var;
+print "<tr ".$bc[$var]."><td width=\"240\">".$langs->trans("CurrentDolibarrLanguage")."</td><td>".$langs->getDefaultLang()."</td></tr>\n";
 print '</table>';
 print '<br>';
 
diff --git a/htdocs/compta/dons/formulaire/fsfe.fr.php b/htdocs/compta/dons/formulaire/fsfe.fr.php
index da3b7c88218c0ba04b83a9372684b518bc569947..d9fe5fab6a405904fc2f91a55172c1e80869b24e 100644
--- a/htdocs/compta/dons/formulaire/fsfe.fr.php
+++ b/htdocs/compta/dons/formulaire/fsfe.fr.php
@@ -17,17 +17,19 @@
  *
  * $Id$
  * $Source$
- *
  */
 
-/*!
+/**
 			\file       htdocs/compta/dons/formulaire/fsfe.fr.php
 			\ingroup    don
 			\brief      Formulaire de don
 			\version    $Revision$
 */
 
-require("../../../main.inc.php");
+require("../../../master.inc.php");
+require("../../../projetdon.class.php");
+require("../../../don.class.php");
+
 
 echo '
 <!DOCTYPE html PUBLIC "-//W3C//DTD HTML 4.0 Transitional//EN" "http://www.w3.org/TR/REC-html40/loose.dtd">
@@ -41,12 +43,6 @@ echo '
 ';
 
 
-
-require("../../../projetdon.class.php");
-require("../../../don.class.php");
-
-setlocale(LC_ALL,$conf->langage);
-
 $don = new Don($db);
 $don->id = $_GET["rowid"];
 $don->fetch($_GET["rowid"]);
diff --git a/htdocs/install/inc.php b/htdocs/install/inc.php
index 35562bf9b9fc4ac95911203195d42635f4b65087..7ed9f65e7c710debef007ba84542a6218a613317 100644
--- a/htdocs/install/inc.php
+++ b/htdocs/install/inc.php
@@ -33,9 +33,10 @@ $conffile = "../conf/conf.php";
 
 
 // Defini objet langs
-require_once("../translate.class.php");
-$langcode='auto';
-$langs = new Translate("../langs", $langcode);
+require_once('../translate.class.php');
+$langs = new Translate('../langs');
+$langs->setDefaultLang('auto');
+$langs->setPhpLang();
 
 
 $tab[0]=' class="bg1"';
diff --git a/htdocs/langs/en_US/admin.lang b/htdocs/langs/en_US/admin.lang
index 07f0d5c8d94b71c18c3818d86932fcd8aa8458bc..4aef4b841138350fa1c5404d17dc0d0a891ff624 100644
--- a/htdocs/langs/en_US/admin.lang
+++ b/htdocs/langs/en_US/admin.lang
@@ -24,6 +24,11 @@ OtherSetup=Other setup
 Modules=Modules
 ModulesCommon=Common modules
 ModulesSpecial=Special modules
+ParameterInDolibarr=Parameter %s
+LanguageParameter=Language parameter %s
+LanguageBrowserParameter=Parameter %s
+LanguageDolibarrParameter=Language Dolibarr parameter
+CurrentDolibarrLanguage=Dolibarr current language
 OSEnv=OS Environment
 Box=Box
 Boxes=Boxes
diff --git a/htdocs/langs/fr_FR/admin.lang b/htdocs/langs/fr_FR/admin.lang
index 2ea1ccfd3a3a25b48772100388c25a375a4abdb5..b43916af6f64573a6c978e1aaa7a247d9244edd7 100644
--- a/htdocs/langs/fr_FR/admin.lang
+++ b/htdocs/langs/fr_FR/admin.lang
@@ -24,6 +24,11 @@ OtherSetup=Divers
 Modules=Modules
 ModulesCommon=Modules standards
 ModulesSpecial=Modules sp�ciaux
+ParameterInDolibarr=Variable %s
+LanguageParameter=Variable langue %s
+LanguageBrowserParameter=Variable %s
+LanguageDolibarrParameter=Param�tre de langue Dolibarr
+CurrentDolibarrLanguage=Langue Dolibarr courante
 OSEnv=Environnement OS
 Box=Bo�te
 Boxes=Bo�tes
diff --git a/htdocs/lib/functions.inc.php b/htdocs/lib/functions.inc.php
index cb792938895b9ceebad3e24bae0e9514ceddc4c9..a2151a905a22df6745b53f7c994eedb87293a4d1 100644
--- a/htdocs/lib/functions.inc.php
+++ b/htdocs/lib/functions.inc.php
@@ -281,34 +281,6 @@ function dolibarr_get_const($db, $name)
 }
 
 
-/**
-		\brief      Positionne environnement PHP en fonction du langage
-		\param	    code_lang       Code langue concern� (fr_FR, en_US, ...)
-		\return     string          Code langue valid�
-*/
-function dolibarr_set_php_lang($code_lang)
-{
-    $code_lang_tiret=ereg_replace('_','-',$code_lang);
-
-    //dolibarr_syslog("dolibarr_set_php_lang: code_lang=$code_lang code_lang_tirer=$code_lang_tiret");
-   
-    setlocale(LC_ALL, $code_lang);    // Compenser pb de locale avec windows
-    setlocale(LC_ALL, $code_lang_tiret);
-    if (defined("MAIN_FORCE_SETLOCALE_LC_ALL") && MAIN_FORCE_SETLOCALE_LC_ALL) setlocale(LC_ALL, MAIN_FORCE_SETLOCALE_LC_ALL);
-    if (defined("MAIN_FORCE_SETLOCALE_LC_TIME") && MAIN_FORCE_SETLOCALE_LC_TIME) setlocale(LC_TIME, MAIN_FORCE_SETLOCALE_LC_TIME);
-    if (defined("MAIN_FORCE_SETLOCALE_LC_NUMERIC") && MAIN_FORCE_SETLOCALE_LC_NUMERIC) setlocale(LC_NUMERIC, MAIN_FORCE_SETLOCALE_LC_NUMERIC);
-    if (defined("MAIN_FORCE_SETLOCALE_LC_MONETARY") && MAIN_FORCE_SETLOCALE_LC_MONETARY) setlocale(LC_MONETARY, MAIN_FORCE_SETLOCALE_LC_MONETARY);
-
-    // On corrige $code_lang si il ne vaut pas le code long: fr -> fr_FR par exemple
-    if (strlen($code_lang) <= 3)
-    {
-        $code_lang = strtolower($code_lang)."_".strtoupper($code_lang);
-    }
-
-    return $code_lang;
-}
-
-
 /**
 		\brief      Insertion d'une constante dans la base de donn�es.
 		\see        dolibarr_del_const, dolibarr_get_const
diff --git a/htdocs/main.inc.php b/htdocs/main.inc.php
index ccd782e21357617a746d75f6a79c8c5f660b1f51..cf521fed76922ba38454e689d044cdf0ccb08cd0 100644
--- a/htdocs/main.inc.php
+++ b/htdocs/main.inc.php
@@ -29,7 +29,7 @@
         \version    $Revision$
 */
 
-require("master.inc.php");
+require_once("master.inc.php");
 
 
 // Verification du login.
@@ -135,12 +135,11 @@ if (isset($user->conf->PRODUIT_LIMIT_SIZE))
 }
 if (isset($user->conf->MAIN_LANG_DEFAULT) && $user->conf->MAIN_LANG_DEFAULT)
 {
-    if ($conf->langage != $user->conf->MAIN_LANG_DEFAULT)
+    if ($langs->getDefaultLang() != $user->conf->MAIN_LANG_DEFAULT)
     {
-        // Si on a un langage perso diff�rent du langage global
-        $conf->langage=dolibarr_set_php_lang($user->conf->MAIN_LANG_DEFAULT);
-    
-        $langs = new Translate(DOL_DOCUMENT_ROOT ."/langs", $conf->langage);
+        // Si on a un langage perso diff�rent du langage courant global
+        $langs->setDefaultLang($user->conf->MAIN_LANG_DEFAULT);
+        $langs->setPhpLang($user->conf->MAIN_LANG_DEFAULT);
     }
 }
 
diff --git a/htdocs/master.inc.php b/htdocs/master.inc.php
index afae9e0cfc4ab34aa6e011a820115b1f83eb71b2..4060255b7a4d3ad55fcfa1bbbffbe871295da063 100644
--- a/htdocs/master.inc.php
+++ b/htdocs/master.inc.php
@@ -5,7 +5,7 @@
  * Copyright (C) 2004      Sebastien Di Cintio  <sdicintio@ressource-toi.org>
  * Copyright (C) 2004      Benoit Mortier       <benoit.mortier@opensides.be>
  * Copyright (C) 2005      Regis Houssin        <regis.houssin@cap-networks.com>
- * Copyright (C) 2005 	   Simon Tosser  <simon@kornog-computing.com> 
+ * Copyright (C) 2005 	   Simon Tosser         <simon@kornog-computing.com> 
  *
  * This program is free software; you can redistribute it and/or modify
  * it under the terms of the GNU General Public License as published by
@@ -158,14 +158,14 @@ if (! $conf->global->MAIN_MENU_BARRELEFT) $conf->global->MAIN_MENU_BARRELEFT="de
 if (! $conf->global->MAIN_MENUFRONT_BARRELEFT) $conf->global->MAIN_MENUFRONT_BARRELEFT="default.php";
 
 /*
- * Positionne le langage global et localisation dans $conf->langage
- * et charge l'objet de traduction
+ * Charge l'objet de traduction et positionne langage courant global 
  */
 if (! $conf->global->MAIN_LANG_DEFAULT) $conf->global->MAIN_LANG_DEFAULT="fr_FR";
-$conf->langage=dolibarr_set_php_lang($conf->global->MAIN_LANG_DEFAULT);
 
 require_once(DOL_DOCUMENT_ROOT ."/translate.class.php");
-$langs = new Translate(DOL_DOCUMENT_ROOT ."/langs", $conf->langage);
+$langs = new Translate(DOL_DOCUMENT_ROOT ."/langs");
+$langs->setDefaultLang($conf->global->MAIN_LANG_DEFAULT);
+$langs->setPhpLang($conf->global->MAIN_LANG_DEFAULT);
 
 
 /*
diff --git a/htdocs/translate.class.php b/htdocs/translate.class.php
index c43bdc77c1130069613d38ab459f02fa20495467..2ac86d77fbe7d5ea10837b7c46f225011b0e3828 100644
--- a/htdocs/translate.class.php
+++ b/htdocs/translate.class.php
@@ -43,12 +43,10 @@ class Translate {
     /**
      *  \brief      Constructeur de la classe
      *  \param      dir             Repertoire racine des fichiers de traduction
-     *  \param      defaultlang     Langue par defaut � utiliser
      */
-    function Translate($dir = "", $defaultlang = "")
+    function Translate($dir = "")
     {
         $this->dir=$dir;
-        $this->setDefaultLang($defaultlang);
     }
 
 
@@ -68,14 +66,45 @@ class Translate {
 
             $langpart=split("_",$langlist[0]);
 
-            if (isset($langpart[1])) $defaultlang=$langpart[0]."_".strtoupper($langpart[1]);
-            else $defaultlang=$langpart[0]."_".strtoupper($langpart[0]);
+            if (isset($langpart[1])) $defaultlang=strtolower($langpart[0])."_".strtoupper($langpart[1]);
+            else $defaultlang=strtolower($langpart[0])."_".strtoupper($langpart[0]);
         }
 
         $this->defaultlang=$defaultlang;
     }
 
     
+    /**
+     *  \brief      Accesseur de this->defaultlang
+     *  \return     string      Langue utilis�e
+     */
+    function getDefaultLang()
+    {
+        return $this->defaultlang;
+    }
+
+    
+    /**
+    		\brief      Positionne environnement PHP en fonction du langage
+    		\remarks    Le code langue long (fr_FR, en_US, ...) doit �tre positionn�
+    		\return     int             >0 si ok, <0 so ko
+    */
+    function setPhpLang()
+    {
+        //dolibarr_syslog("Translate::set_php_lang: code_lang=$code_lang code_lang_tirer=$code_lang_tiret");
+       
+        $code_lang_tiret=ereg_replace('_','-',$this->defaultlang);
+        setlocale(LC_ALL, $this->defaultlang);    // Compenser pb de locale avec windows
+        setlocale(LC_ALL, $code_lang_tiret);
+        if (defined("MAIN_FORCE_SETLOCALE_LC_ALL") && MAIN_FORCE_SETLOCALE_LC_ALL) setlocale(LC_ALL, MAIN_FORCE_SETLOCALE_LC_ALL);
+        if (defined("MAIN_FORCE_SETLOCALE_LC_TIME") && MAIN_FORCE_SETLOCALE_LC_TIME) setlocale(LC_TIME, MAIN_FORCE_SETLOCALE_LC_TIME);
+        if (defined("MAIN_FORCE_SETLOCALE_LC_NUMERIC") && MAIN_FORCE_SETLOCALE_LC_NUMERIC) setlocale(LC_NUMERIC, MAIN_FORCE_SETLOCALE_LC_NUMERIC);
+        if (defined("MAIN_FORCE_SETLOCALE_LC_MONETARY") && MAIN_FORCE_SETLOCALE_LC_MONETARY) setlocale(LC_MONETARY, MAIN_FORCE_SETLOCALE_LC_MONETARY);
+    
+        return 1;
+    }
+
+
     /**
 	 *  \brief      Charge en m�moire le tableau de traduction pour un domaine particulier
      *              Si le domaine est deja charg�, la fonction ne fait rien