« MODx Parse Error »

MODx encountered the following error while attempting to parse the requested resource:
« PHP Parse Error »
PHP error debug
  Error: file_get_contents(http://www.confern.de/common/Partnergesamtliste_Deutschland.json): failed to open stream: HTTP request failed! HTTP/1.1 503 Service Temporarily Unavailable  
  Error type/ Nr.: Warning - 2 
  File: /usr/www/users/krichler/modx/manager/includes/document.parser.class.inc.php(800) : eval()'d code 
  Line: 2 
Parser timing
  MySQL: 0,0075 s(29 Requests)
  PHP: 0,1697 s 
  Total: 0,1772 s