[Zope] CMF : customize actions/user

hello I try to find how to customize the "actions" label. they are used for writing : Login, Join, My stuff, ... ZPT skin define some : user_actions actions/user folder_actions actions/folder I'd have a look in all document in CMF Site, but found nothing. Perjaps that Labels are hardcoded ... I'm shure we can customize them ! ;o) Thanks