PHP Fatal Error in core/cache

<?php
function elements_modsnippet_4($scriptProperties= array()) {
global $modx;
if (is_array($scriptProperties)) {
extract($scriptProperties, EXTR_SKIP);
}
/**
 * Login
 *
 * Copyright 2010 by Jason Coward <[email protected]> and Shaun McCormick
 * <[email protected]>
 *
 * Login is free software; you can redistribute it and/or modify it
 * under the terms of the GNU General Public License as published by the Free
 * Software Foundation; either version 2 of the License, or (at your option) any
 * later version.
 *
 * Login is distributed in the hope that it will be useful, but WITHOUT ANY
 * WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS FOR
 * A PARTICULAR PURPOSE. See the GNU General Public License for more details.
 *
 * You should have received a copy of the GNU General Public License along with
 * Login; if not, write to the Free Software Foundation, Inc., 59 Temple
 * Place, Suite 330, Boston, MA 02111-1307 USA
 *
 * @package login
 */
/**
 * MODx Login Snippet
 *
 * This snippet handles login POSTs, sending the user back to where they came from or to a specific
 * location if specified in the POST.
 *
 * @package login
 *
 * @property textfield actionKey The REQUEST variable containing the action to take.
 * @property textfield loginKey The actionKey for login.
 * @property textfield logoutKey The actionKey for logout.
 * @property list tplType The type of template to expect for the views:
 *  modChunk - name of chunk to use
 *  file - full path to file to use as tpl
 *  embedded - the tpl is embedded in the page content
 *  inline - the tpl is inline content provided directly
 * @property textfield loginTpl The template for the login view (content based on tplType)
 * @property textfield logoutTpl The template for the logout view (content based on tplType)
 * @property textfield errTpl The template for any errors that occur when processing an view
 * @property list errTplType The type of template to expect for the error messages:
 *  modChunk - name of chunk to use
 *  file - full path to file to use as tpl
 *  inline - the tpl is inline content provided directly
 * @property integer logoutResourceId An explicit resource id to redirect users to on logout
 * @property string loginMsg The string to use for the login action. Defaults to
 * the lexicon string "login".
 * @property string logoutMsg The string to use for the logout action. Defaults
 * to the lexicon string "login.logout"
 */
require_once $modx->getOption('login.core_path',null,$modx->getOption('core_path').'components/login/').'model/login/login.class.php';
$login = new Login($modx,$scriptProperties);
if (!is_object($login) || !($login instanceof Login)) return '';

$controller = $login->loadController('Login');
$output = $controller->run($scriptProperties);
return $output;
}