diff --git a/main/inc/lib/chamilo_session.class.php b/main/inc/lib/chamilo_session.class.php
index db22a88a12..4f8facff6c 100755
--- a/main/inc/lib/chamilo_session.class.php
+++ b/main/inc/lib/chamilo_session.class.php
@@ -52,9 +52,7 @@ class ChamiloSession extends System\Session
      */
     public static function session_lifetime()
     {
-        global $_configuration;
-
-        return $_configuration['session_lifetime'];
+        return api_get_configuration_value('session_lifetime');
     }
 
     /**