diff --git a/fonctions.php b/fonctions.php
index 0088e00..db738a4 100644
--- a/fonctions.php
+++ b/fonctions.php
@@ -111,7 +111,7 @@ function is_error($cerr)
 
 function is_user()
 {
-  return isset($_SERVER['REMOTE_USER']) || (isset($_SESSION['nom']));
+  return ( USE_REMOTE_USER && isset($_SERVER['REMOTE_USER']) ) || (isset($_SESSION['nom']));
 }
 
 
diff --git a/infos_sondage.php b/infos_sondage.php
index 9c56dea..1384d1a 100644
--- a/infos_sondage.php
+++ b/infos_sondage.php
@@ -192,7 +192,7 @@ if ($erreur_injection_commentaires) {
 echo '</tr>'."\n";
 echo '<tr><td>'. _("Your name*: ") .'</td><td>';
 
-if (isset($_SERVER['REMOTE_USER'])) {
+if (USE_REMOTE_USER && isset($_SERVER['REMOTE_USER'])) {
   echo '<input type="hidden" name="nom" size="40" maxlength="40" value="'.$_SESSION["nom"].'">'.stripslashes($_SESSION["nom"]).'</td>'."\n";
 } else {
   echo '<input type="text" name="nom" size="40" maxlength="40" value="'.stripslashes($_SESSION["nom"]).'"></td>'."\n";
@@ -207,7 +207,7 @@ if (!$_SESSION["nom"] && issetAndNoEmpty("poursuivre")) {
 echo '</tr>'."\n";
 echo '<tr><td>'. _("Your e-mail address *: ") .'</td><td>';
 
-if (isset($_SERVER['REMOTE_USER'])) {
+if (USE_REMOTE_USER && isset($_SERVER['REMOTE_USER'])) {
   echo '<input type="hidden" name="adresse" size="40" maxlength="64" value="'.$_SESSION["adresse"].'">'.$_SESSION["adresse"].'</td>'."\n";
 } else {
   echo '<input type="text" name="adresse" size="40" maxlength="64" value="'.$_SESSION["adresse"].'"></td>'."\n";
@@ -269,4 +269,4 @@ echo '</form>'."\n";
 //bandeau de pied
 bandeau_pied();
 echo '</body>'."\n";
-echo '</html>'."\n";
\ No newline at end of file
+echo '</html>'."\n";
diff --git a/studs.php b/studs.php
index fd89460..190b52a 100644
--- a/studs.php
+++ b/studs.php
@@ -136,7 +136,7 @@ if (!is_error(NO_POLL) && (isset($_POST["boutonp"]) || isset($_POST["boutonp_x"]
     $err |= NAME_EMPTY;
   }
   
-  if(!is_error(NAME_EMPTY) && (!isset($_SERVER['REMOTE_USER']) || $_POST["nom"] == $_SESSION["nom"])) {
+  if(!is_error(NAME_EMPTY) && (! ( USE_REMOTE_USER && isset($_SERVER['REMOTE_USER']) ) || $_POST["nom"] == $_SESSION["nom"])) {
     $nouveauchoix = '';
     for ($i=0;$i<$nbcolonnes;$i++) {
       // Si la checkbox est enclenchée alors la valeur est 1
@@ -444,7 +444,7 @@ while ($data = $user_studs->FetchNextObject(false)) {
   $ensemblereponses = $data->reponses;
   
   // ligne d'un usager pré-authentifié
-  $mod_ok = !isset($_SERVER['REMOTE_USER']) || ($nombase == $_SESSION['nom']);
+  $mod_ok = !( USE_REMOTE_USER && isset($_SERVER['REMOTE_USER']) ) || ($nombase == $_SESSION['nom']);
   $user_mod |= $mod_ok;
   
   // pour chaque colonne
@@ -490,7 +490,7 @@ while ($data = $user_studs->FetchNextObject(false)) {
 }
 
 // affichage de la ligne pour un nouvel utilisateur
-if (!isset($_SERVER['REMOTE_USER']) || !$user_mod) {
+if (! ( USE_REMOTE_USER && isset($_SERVER['REMOTE_USER']) ) || !$user_mod) {
   echo '<tr class="ajout_reponse">'."\n";
   echo '<td class="nom">'."\n";
   if (isset($_SESSION['nom'])) {
diff --git a/variables.php.template b/variables.php.template
index 7a1214c..2847125 100644
--- a/variables.php.template
+++ b/variables.php.template
@@ -81,6 +81,9 @@ define('URL_PROPRE', false);
 // Activation de Google Analytics (false si inactif, l'identifiant sinon)
 define('GOOGLE_ANALYTICS_ID', false);
 
+// Utilisation de l'identité (REMOTE_USER) fournie par le serveur web
+define('USE_REMOTE_USER', true);
+
 if (@file_exists('variables.local.php')) {
     include('variables.local.php');
 }