public function validateUri($uri)
    {
        $query = http_build_query(array_merge(
            $this->getOptions()->buildOptions(),
            array('uri' => $uri)
        ));

        $context = stream_context_create(array(
            'http' => array(
                'method' => 'GET',
                'header' => 'User-Agent: HTMLValidator',
            )
        ));

        $data = $this->sendRequest($this->validatorUri . '?' . $query, $context);

        return $this->parseSOAP12Response($data);
    }