diff --git a/htdocs/lib/security.lib.php b/htdocs/lib/security.lib.php
index 62f1eb1f48a..3b4cf5d14c1 100644
--- a/htdocs/lib/security.lib.php
+++ b/htdocs/lib/security.lib.php
@@ -78,9 +78,13 @@ function dol_loginfunction($langs,$conf,$mysoc)
 
 	$conf->css = "/theme/".$conf->theme."/style.css.php?lang=".$langs->defaultlang;
 	$conf_css = DOL_URL_ROOT.$conf->css;
+	
+	// Add real path in session name
+	$realpath='';
+	if ( preg_match('/^([^.]+)\/htdocs\//i', realpath($_SERVER["SCRIPT_FILENAME"]), $regs))	$realpath = isset($regs[1])?$regs[1]:'';
 
 	// Set cookie for timeout management
-	$sessiontimeout='DOLSESSTIMEOUT_'.md5($_SERVER["SERVER_NAME"].$_SERVER["DOCUMENT_ROOT"]);
+	$sessiontimeout='DOLSESSTIMEOUT_'.md5($_SERVER["SERVER_NAME"].$_SERVER["DOCUMENT_ROOT"].$realpath);
 	if (! empty($conf->global->MAIN_SESSION_TIMEOUT)) setcookie($sessiontimeout, $conf->global->MAIN_SESSION_TIMEOUT, 0, "/", '', 0);
 
 	if (! empty($_REQUEST["urlfrom"])) $_SESSION["urlfrom"]=$_REQUEST["urlfrom"];