diff --git a/www/libs/Class.Basic.inc b/www/libs/Class.Basic.inc
index 755c7ef2..363bf380 100644
--- a/www/libs/Class.Basic.inc
+++ b/www/libs/Class.Basic.inc
@@ -312,7 +312,7 @@
 			if (!session_id())
 			{
 				// check if we have an external session name given, else skip this step
-				if (isset(SET_SESSION_NAME))
+				if (isset($GLOBALS['SET_SESSION_NAME']))
 				{
 					// set the session name for possible later check
 					$this->session_name = SET_SESSION_NAME;