title: when i try $this->Auth->user() it work but when i add id $this->Auth->user('id') it don't work it is null
body: <p>$this->Auth->user('id')  always null
  appcontrollers code :</p>
  
  <pre><code>&lt;?php
   App::uses('AuthComponent', 'Controller/Component');
   App::uses('Controller', 'Controller');
   class AppController extends Controller {
  //public $components = array('DebugKit.Toolbar','Session');
    public $components = array(
      'Acl',
      'Flash',
      'Auth' =&gt; array(
          'authorize' =&gt; array(
              'Actions' =&gt; 
         array('actionPath' =&gt; 'controllers','action'=&gt;'index')
          )
      ),
      'Session'
  );
  public $helpers = array('Html', 'Form', 'Session');
  
  public function beforeFilter() {
      //Configure AuthComponent
      $this-&gt;Auth-&gt;allow();
      $this-&gt;Auth-&gt;loginAction = array(
        'controller' =&gt; 'personnes',
        'action' =&gt; 'login'
      );
      $this-&gt;Auth-&gt;logoutRedirect = array(
        'controller' =&gt; 'personnes',
        'action' =&gt; 'login'
      );
      $this-&gt;Auth-&gt;loginRedirect = array(
        'controller' =&gt; 'biens',
        'action' =&gt; 'index'
      ); }}
  </code></pre>
  
  <p>Personnescontrollers</p>
  
  <pre><code>public function beforeFilter() {
  parent::beforeFilter();
  
  $this-&gt;Auth-&gt;allow();
   }
  
  public function login() {
  if ($this-&gt;request-&gt;is('post')) {
       $user = $this-&gt;Personne-&gt;findAllByLoginAndMdp
    ($this-&gt;data['Personne']['login'],$this-&gt;data['Personne']['mdp']);
  
      if ($this-&gt;Auth-&gt;login($user)) {
     return $this-&gt;redirect($this-&gt;Auth-&gt;redirectUrl()); 
  
       } else {
          $this-&gt;Session-&gt;setFlash(__
         ('Votre nom d\'user ou mot de passe sont incorrects.'));
         }
       }
       }
  </code></pre>
  
  <p>bienscONTROLLERS</p>
  
  <pre><code>     public function index( ) {
       $this-&gt;Bien-&gt;recursive = 0;
        $this-&gt;paginate = array(
        'paramType' =&gt; 'querystring',
      'limit' =&gt; 5
          );
        $biens = $this-&gt;paginate('Bien');
        $this-&gt;set(compact('biens'));
      $user = $this-&gt;Auth-&gt;user('id');
      Debugger::dump($user);
       }
  </code></pre>
  
  <p>Personne model`</p>
  
  <pre><code>&lt;?php
      App::uses('AuthComponent', 'Controller/Component');
       App::uses('AppModel', 'Model');
       class Personne extends AppModel {`
        public function beforeSave($options = array()) {
        $this-&gt;data['Personne']['mdp'] = 
        AuthComponent::password($this&gt;data['Personne']['mdp']);
         return true;
         }
  </code></pre>
  
  <p>when i try $this->Auth->user() it work but when i add id $this->Auth->user()'id' it don't work 
  Plz what can i do ? can someone help me ?</p>