Index: includes/session.php
===================================================================
--- includes/session.php	(Revision 9654)
+++ includes/session.php	(Arbeitskopie)
@@ -1833,7 +1833,7 @@
 
 		// Does the user need to change their password? If so, redirect to the
 		// ucp profile reg_details page ... of course do not redirect if we're already in the ucp
-		if (!defined('IN_ADMIN') && !defined('ADMIN_START') && $config['chg_passforce'] && $this->data['is_registered'] && $auth->acl_get('u_chgpasswd') && $this->data['user_passchg'] < time() - ($config['chg_passforce'] * 86400))
+		if (!defined('IN_ADMIN') && !defined('ADMIN_START') && $config['chg_passforce'] && isset($this->data['is_registered']) && $this->data['is_registered'] && $auth->acl_get('u_chgpasswd') && $this->data['user_passchg'] < time() - ($config['chg_passforce'] * 86400))
 		{
 			if (strpos($this->page['query_string'], 'mode=reg_details') === false && $this->page['page_name'] != "ucp.$phpEx")
 			{