FriendsOfSymfony/FOSFacebookBundle — Issue #119: Symfony\Component\Security\Core\Authentication\Token\UsernamePasswordToken::serialize() must return a string or NULL
Author: Raulken
Created: 2012-02-16 22:29:30+00:00
State: open

this in user bundle give to me this error

User.php
public function serialize()
{
return serialize(array($this->facebookId, parent::serialize()));
}

public function unserialize($data)
{
list($this->facebookId, $parentData) = unserialize($data);
parent::unserialize($parentData);
}

how i can fix?