<?php
class EDM_Auth extends Zend_Auth
{
    protected static $_instance = null;

    public static function getInstance()
    {
        if (null === self::$_instance) {
            self::$_instance = new self();

            self::$_instance->setStorage(new Zend_Auth_Storage_Session('userAuth'));;
            if (!$this->hasIdentity()) {
			$this->getStorage()->write(array('user_level_id'=>0));
		}
        }
        return self::$_instance;
}