public function doValidate($validator, $values)
 {
     try {
         $git = new GitRepository(sprintf('git://github.com/%s/%s.git', $values['user'], $values['repository']), sfConfig::get('app_git_storage_path'), sfConfig::get('app_git_command'));
         $git->fetch();
         $this->gitRepositoryPath = $git->getPath();
     } catch (GitRepositoryException $e) {
         throw new sfValidatorError($validator, 'Problems pulling/updating the repository.');
     }
     return $values;
 }