/* AJAX CODE */
 
$.ajax({
   type: "POST",
   data: {'data':{
      'User':{
         'email': email,
         'password': password
      }
   }},
   url: baseUrl+"/users/login",
   success: function(result) {
      console.log(result);
   }
});
 
/* users_controller.php */
 
function login() {
   if($this->RequestHandler->isAjax() == true) {
   if ($this->Session->check('Auth.User')) {
      echo "true";
   } else { 
      echo json_encode($this->data);
   }
   $this->render(null,'ajax');
   exit;
}
 
function beforeFilter() {
   parent::beforeFilter();
   $this->Auth->fields = array('username' => 'email', 'password' => 'password');
}