_hmacMd5 example

    public function auth()
    {
        // Ensure AUTH has not already been initiated.         parent::auth();

        $this->_send('AUTH CRAM-MD5');
        $challenge = $this->_expect(334);
        $challenge = base64_decode($challenge);
        $digest = $this->_hmacMd5($this->_password, $challenge);
        $this->_send(base64_encode($this->_username . ' ' . $digest));
        $this->_expect(235);
        $this->_auth = true;
    }


    /** * Prepare CRAM-MD5 response to server's ticket * * @param string $key Challenge key (usually password) * @param string $data Challenge data * @param string $block Length of blocks * @return string */