CakePHP自定义登录和OPAuth

Question

I have successfully implemented Opauth for CakePHP for Google & Facebook.
On the original return, they write info to the database including auth_id & auth_method as well as being assigned as user_id.
This is working correctly
On all succeeding returns it should log the user in.
I also have a basic email & password login running at the same time.
To get the user I use:

$user = $this->User->find('first', array(
            'conditions' => array('User.auth_id' => $this->data['auth']['uid'],
                                    'User.auth_method' => 2)));

This returns a user, but the following always returns false:

$this->Auth->login($user)

I have also tried

login($user['User']), login($user['User']['user_id'])

But does not work... Any hints?