[Zope] Folder name from URL etc.

Hello all, How do I go from a URL to an object name? I have acl_users folders defined at different levels and I would like to use AUTHENTICATION_PATH to find out what level a user has authorization up to. At each folder level I have a 'Messages' folder and I'd like to display the contents of the correct folder depending on the users' clearance/home folder. TIA. Regards, Samir