Index: units/email_events/email_events_event_handler.php
===================================================================
--- units/email_events/email_events_event_handler.php	(revision 13652)
+++ units/email_events/email_events_event_handler.php	(working copy)
@@ -356,6 +356,10 @@
 					$user->Load($to_user_id);
 				}
 			}
+			elseif (is_numeric($to_user_id)) {
+				// recipient is system user with negative ID (root, guest, etc.) -> send to admin
+				array_unshift($all_recipients[RECIPIENT_TYPE_TO], $this->_getDefaultRepipient());
+			}
 
 			// update with custom data given during event execution (email + name)
 			$add_recipient = Array ();
@@ -376,11 +380,7 @@
 
 			if (($object->GetDBField('Type') == EVENT_TYPE_ADMIN) && !$all_recipients[RECIPIENT_TYPE_TO]) {
 				// admin email event without direct recipient -> send to admin
-				$all_recipients[RECIPIENT_TYPE_TO][] = Array (
-					'RecipientName' => $this->Application->ConfigValue('Smtp_AdminMailFrom'),
-					'RecipientAddressType' => ADDRESS_TYPE_EMAIL,
-					'RecipientAddress' => $this->Application->ConfigValue('Smtp_AdminMailFrom'),
-				);
+				array_unshift($all_recipients[RECIPIENT_TYPE_TO], $this->_getDefaultRepipient());
 			}
 
 			$esender =& $this->Application->recallObject('EmailSender');
@@ -468,6 +468,20 @@
 		}
 
 		/**
+		 * This is default recipient, when we can't determine actual one
+		 *
+		 * @return Array
+		 */
+		function _getDefaultRepipient()
+		{
+			return Array (
+				'RecipientName' => $this->Application->ConfigValue('Smtp_AdminMailFrom'),
+				'RecipientAddressType' => ADDRESS_TYPE_EMAIL,
+				'RecipientAddress' => $this->Application->ConfigValue('Smtp_AdminMailFrom'),
+			);
+		}
+
+		/**
 		 * Returns email event message by ID (headers & body in one piece)
 		 *
 		 * @param kEvent $event