protected function check($challengeField, $responseField) {
        
        $server = $this->request->server;
        
        $data = array(
            'privatekey' => $this->options['private_key'],
            'remoteip'   =>  $server->get('REMOTE_ADDR') ,
            'challenge'  => $challengeField,
            'response'   => $responseField     
        );
        
        $curl = curl_init($this->options['verify_url']);
        curl_setopt($curl, CURLOPT_POST, true);
        curl_setopt($curl, CURLOPT_RETURNTRANSFER, true);
        curl_setopt($curl, CURLOPT_CONNECTTIMEOUT, 10);
        curl_setopt($curl, CURLOPT_HTTP_VERSION, CURL_HTTP_VERSION_1_0);
        curl_setopt($curl, CURLOPT_USERAGENT, 'reCAPTCHA/PHP');
        curl_setopt($curl, CURLOPT_POSTFIELDS, $data);
        curl_setopt($curl, CURLOPT_HEADER, true);
        $response = curl_exec($curl);

        $response = explode("\r\n\r\n", $response, 2);

        return (isset($response[1]) && preg_match('/true/', $response[1]));       
    }