title: CakePHP auth component doesn't login users
body: <p>this is my AppController.php</p>
  
  <pre><code>class AppController extends Controller {
      public $components = array(
          'Session',
          'Auth' =&gt; array(
              'loginAction' =&gt; array(
                  'controller' =&gt; 'students',
                  'action' =&gt; 'login'
              ),
              'loginRedirect' =&gt; array('controller' =&gt; 'students', 'action' =&gt; 'index'),
              'logoutRedirect' =&gt; array('controller' =&gt; 'students', 'action' =&gt; 'login'),
              'authError' =&gt; "You can't acces that page",
              'authorize' =&gt; array('controller')
          )
      );
  
      public function isAuthorized($student){
          return TRUE;
      }
  }
  </code></pre>
  
  <p>this is my StudentsController.php</p>
  
  <pre><code>class StudentsController extends AppController{
  
  
          public function login(){
              if($this-&gt;request-&gt;is('post')){
                  if($this-&gt;Auth-&gt;login()){
                      $this-&gt;redirect($this-&gt;Auth-&gt;redirect());
                  }else{
                      $this-&gt;Session-&gt;setFlash('Your username or password is incorrect');
                  }
              }
          }
  
          public function logout(){
              $this-&gt;redirect($this-&gt;Auth-&gt;logout());
          }
  }
  </code></pre>
  
  <p>this is my login.ctp</p>
  
  <pre><code>&lt;h2&gt;Login&lt;/h2&gt;
  &lt;?php
      echo $this-&gt;Form-&gt;create();
      echo $this-&gt;Form-&gt;input('username');
      echo $this-&gt;Form-&gt;input('password');
      echo $this-&gt;Form-&gt;end('Login');
  ?&gt;
  </code></pre>
  
  <p>and in my db the table name is <em>students</em> and its fields are <em>username</em> and <em>password</em>.</p>
  
  <p>But every time I try to login with <code>$this-&gt;Auth-&gt;login()</code>, it returns false and password wrong flash message is showing and I cannot login.</p>