Add to ErrorHTTPException support code 401.

exception/ErrorHTTPException.php

@@ -15,6 +15,7 @@ class ErrorHTTPException extends GeneralException
     {
         $this->http_headers = array(
                     400 => 'HTTP/1.0 400 Bad Request',
+                    401 => 'HTTP/1.0 400 Access allowed only for registered users',
                     402 => 'HTTP/1.0 402 Payment Required',
                     403 => 'HTTP/1.0 403 Forbidden',
                     404 => 'HTTP/1.0 404 Not Found',