500 Server Error

A misconfiguration on the server caused a hiccup. Check the server logs, fix the problem, then try again.
URL: http://images.lusoft.idv.tw/500.shtml

Warning: Use of undefined constant DOCUMENT_ROOT - assumed 'DOCUMENT_ROOT' (this will throw an Error in a future version of PHP) in /home/lusoftid/images.lusoft.idv.tw/500.php on line 12

Warning: Use of undefined constant REQUEST_URI - assumed 'REQUEST_URI' (this will throw an Error in a future version of PHP) in /home/lusoftid/images.lusoft.idv.tw/500.php on line 12