« MODx Parse Error »

MODx encountered the following error while attempting to parse the requested resource:
« PHP Parse Error »
 
PHP error debug
  Error: array_key_exists() expects parameter 2 to be array, null given 
  Error type/ Nr.: Warning - 2 
  File: /home/virtwww/w_mapros-a-ru_d8fa1365/http/manager/includes/document.parser.class.inc.php 
  Line: 929 
  Line 929 source: if (!is_numeric($identifier) && array_key_exists($identifier, $this->documentListing)) {  
 
Parser timing
  MySQL: 0.0039 s(2 Requests)
  PHP: 0.0078 s 
  Total: 0.0117 s