[Zope] Get all user folder instances

Hi I'm try to know the complet list of users in a Zope point with this structure: root acl_users (user folder) Folder1 acl_users (Pluggable user folder) Folder2 acl_users (Another user folder) Object1 Object2 how could I retrive the list of user folders (in this case: /acl_users, /Folder1/acl_users and /Folder1/Folder2/acl_users) It would be perfect something like: Object1.superValues('User Folder') But this only retrive User Folder's not Pluggable user folder's nor Another user folder's Is there any kind of method to query for security list of users? Thanks a lot!!