Gmail smtp 5.5.2 error with PHP ZEND and Xoauth2 - php

Question

I trying to send emails with Gmail using gmail api with xoauth authentication.
The IMAP example from google works fine.
I am trying to implement the thing based on these articles:
http://www.boxuk.com/blog/php-smtp-xoauth2-gmail/
http://www.chargenevier.com/2013/02/google-smtp-and-oauth2-authentication/
I get the following error when i try to send the email:
Fatal error: Uncaught exception 'Zend_Mail_Protocol_Exception' with message '5.5.2 Syntax error. e5sm17066681bkg.3 - gsmtp
I also tried the openssl method on the first article, after write in XOAUTH2 i get the same error from the server and connection is closed.
Interesting when i do echo base64_encode("user=\1auth=Bearer \1\1") i got a string whitch is more shorter than that when i echo the $smtpInitClientRequestEncoded variable what is generated with constructAuthString method, what is working fine in the IMAP example.
And mail.google.com gives 5.5.2 Cannot decode response for the shorter encoded string.
function constructAuthString($email, $accessToken) {
return base64_encode("user=$email\1auth=Bearer $accessToken\1\1");
}
function sendEmail($email,$accessToken){
$smtpInitClientRequestEncoded = constructAuthString($email, $accessToken);
echo '<br/><br/>BASE64: ' . $smtpInitClientRequestEncoded;
$config = array('ssl' => 'ssl',
'port' => '465',
'auth' => 'xoauth',
'xoauth_request' => $smtpInitClientRequestEncoded
);
$transport = new Zend_Mail_Transport_Smtp('smtp.gmail.com', $config);
$mail = new Zend_Mail();
$mail->setBodyText('some body text');
$mail->setFrom($email, 'Some Sender');
$mail->addTo("myemail#gmail.com", 'Some Recipient');
$mail->setSubject('Test sending by smtp');
$mail->send($transport);
}
What do you think, what is wrong? Why dont this authenticates?

Answer 1

$accesToken was bad. I passed $client->getAccessToken(), but you need just the access_token string from this string, not the whole.