Modular.php

<?php
class Endo_Controller_Plugin_Modular extends Zend_Controller_Plugin_Abstract
{
    public function preDispatch(Zend_Controller_Request_Abstract $request)
    {
        $module = $request->getModuleName();
        $module = empty($module) ? 'frontend' : $request->getModuleName();
        $namespace = Zend_Auth_Storage_Session::NAMESPACE_DEFAULT;
        $member    = Zend_Auth_Storage_Session::MEMBER_DEFAULT
            . '-' . $module;
        $storage   = new Zend_Auth_Storage_Session($namespace, $member);
        Zend_Auth::getInstance()->setStorage($storage);
    }
}