public function testResourceHeadError()
 {
     $backend = new ezcWebdavMemoryBackend(false);
     $backend->addContents(array('foo' => 'bar', 'bar' => array('blubb' => 'Somme blubb blubbs.')));
     $request = new ezcWebdavHeadRequest('/unknown');
     $request->validateHeaders();
     $response = $backend->head($request);
     $this->assertEquals(new ezcWebdavErrorResponse(ezcWebdavResponse::STATUS_404, '/unknown'), $response, 'Expected response does not match real response.', 0, 20);
 }