public function headURL($url, $followRedirects = true, $username = null, $password = null, $headers = array())
    {

        if (function_exists('curl_init')) {

                $contents = $this->curlRequest($url, true, $followRedirects, $username, $password, $headers);
                return $contents;

        } else {

            throw new HttpRequestException('headURL not supported without curl');

        }
    }