Index: branches/5.2.x/core/units/system_event_subscriptions/system_event_subscription_tp.php
===================================================================
diff -u -N -r15274 -r15290
--- branches/5.2.x/core/units/system_event_subscriptions/system_event_subscription_tp.php	(.../system_event_subscription_tp.php)	(revision 15274)
+++ branches/5.2.x/core/units/system_event_subscriptions/system_event_subscription_tp.php	(.../system_event_subscription_tp.php)	(revision 15290)
@@ -1,6 +1,6 @@
 <?php
 /**
- * @version	$Id: system_event_subscription_tp.php 15274 2012-04-05 13:15:10Z alex $
+ * @version	$Id: system_event_subscription_tp.php 15290 2012-04-11 16:21:33Z alex $
  * @package	In-Portal
  * @copyright	Copyright (C) 1997 - 2012 Intechnic. All rights reserved.
  * @license	  GNU/GPL
@@ -217,11 +217,16 @@
 	 *
 	 * @return string
 	 * @access protected
+	 * @throws Exception
 	 */
 	protected function _getPrefix()
 	{
 		$event = new kEvent($this->_subscriptions->GetDBField('BindToSystemEvent'));
 
+		if ( !$event->Prefix ) {
+			throw new Exception('Subscription "<strong>#' . $this->_subscriptions->GetID() . '</strong>" is connected to invalid or missing e-mail event "<strong>#' . $this->_subscriptions->GetDBField('EmailEventId') . '</strong>"');
+		}
+
 		return $event->Prefix;
 	}