all action under an admin module, how to redirect to the self-defined loginUrl


I’d like to build an admin control panel, and then I define an adminUser(extends CWebUser),

As Yii::app()->user has been used for the frontend,I have to use adminModule->addComponent(‘user’, new adminUser) to define the web user as the admin user.

How can I make the unauthorized action be redirected to adminModule->user->loginUrl instead of /site/login?

tks a lot!!