Index: trunk/core/kernel/db/db_event_handler.php
===================================================================
diff -u -r3597 -r3613
--- trunk/core/kernel/db/db_event_handler.php	(.../db_event_handler.php)	(revision 3597)
+++ trunk/core/kernel/db/db_event_handler.php	(.../db_event_handler.php)	(revision 3613)
@@ -464,8 +464,11 @@
 				if(!$per_page)
 				{
 
-					if ( $config_mapping ) {
-							$per_page = $this->Application->ConfigValue($config_mapping['PerPage']);
+					if ($config_mapping) {
+						if (!isset($config_mapping['PerPage'])) {
+							trigger_error('Incorrect mapping of <span class="debug_error">PerPage</span> key in config for prefix <b>'.$event->Prefix.'</b>', E_USER_WARNING);
+						}
+						$per_page = $this->Application->ConfigValue($config_mapping['PerPage']);
 					}
 					if(!$per_page) $per_page = 10;
 				}