public function getStatus($messageId)
    {
        if (null === $this->username || null === $this->password || null === $this->accountRef) {
            throw new Exception\InvalidCredentialsException('No API credentials provided');
        }

        $params = $this->getParameters(array(
            'messageID' => $messageId,
        ));

        return $this->executeQuery(self::SMS_STATUS_URL, $params);
    }