[Zope] User_Management - Two Folders in different branches

I have a basic Problem with ZOPE USER MANAGEMENT Roles on our site root: Anonymous User Author Editor Manager Owner Okay... lets say I have one folder /users/John_Doe/ with an acl_users folder in it with one user (John_Doe). After John_Doe knows his way around Zope well enough I am going to let him take over a branch of our website e.g. /clinics/pathology/ How do I grant him access to that area of the site without having to create another acl_users in that folder? (A single password and account per user would be nice, as well as a single password_change mechanism for all users) Would a the LDAPLoginAdapter solve my problems (does it allow one account access to specific folders in different branches of a site)? Carl