Dropdown menu werkt niet in Internet Explorer (10)

<?php /** * @package Joomla.Site * @copyright Copyright (C) 2005 - 2012 Open Source Matters, Inc. All rights reserved. * @license GNU General Public License version 2 or later; see LICENSE.txt */ // Set flag that this is a parent file. define('_JEXEC', 1); define('DS', DIRECTORY_SEPARATOR); if (file_exists(dirname(__FILE__) . '/defines.php')) { include_once dirname(__FILE__) . '/defines.php'; } if (!defined('_JDEFINES')) { define('JPATH_BASE', dirname(__FILE__)); require_once JPATH_BASE.'/includes/defines.php'; } require_once JPATH_BASE.'/includes/framework.php'; // Mark afterLoad in the profiler. JDEBUG ? $_PROFILER->mark('afterLoad') : null; // Instantiate the application. $app = JFactory::getApplication('site'); // Initialise the application. $app->initialise(); // Mark afterIntialise in the profiler. JDEBUG ? $_PROFILER->mark('afterInitialise') : null; // Route the application. $app->route(); // Mark afterRoute in the profiler. JDEBUG ? $_PROFILER->mark('afterRoute') : null; // Dispatch the application. $app->dispatch(); // Mark afterDispatch in the profiler. JDEBUG ? $_PROFILER->mark('afterDispatch') : null; // Render the application. $app->render(); // Mark afterRender in the profiler. JDEBUG ? $_PROFILER->mark('afterRender') : null; // Return the response. echo $app;