Login externo no joomla framework

external-login.php

<?php
define('_JEXEC', 1);
define('JPATH_BASE', '../');
define('DS', DIRECTORY_SEPARATOR);
require_once('../configuration.php');
require_once(JPATH_BASE . DS . 'includes' . DS . 'defines.php');
require_once(JPATH_BASE . DS . 'includes' . DS . 'framework.php');

$mainframe = JFactory::getApplication('site');
$mainframe->initialise();

$login = '<SeuLogin>';
$email = '<SeuEmail>';
function getUser($login, $email)
{
   $db = JFactory::getDbo();
   $query = $db
      ->getQuery(true)
      ->select('*')
      ->from($db->quoteName('#__users'))
      ->where($db->quoteName('username') . " = " . $db->quote($login))
      ->andWhere($db->quoteName('email') . " = " . $db->quote($email));

   $db->setQuery($query);
   return $db->loadObject();
}
$user = getUser($login, $email);
var_dump($user);

$credentials = array(
   'username' => $user->username,
   'password' => '<PASSWORD>'
);
$logged = $mainframe->login($credentials);