[Zope] Assigning Roles to Roles

Has the been any consideration to adding the ability to give Roles to Roles? I'm thinking of a situation where I assign the roles Staff and Student in the root of my site. In some sub folder I may want to say all Staff and Students are managers. I don't want to maintain the permissions for both Staff and Students, only for Manager. I think Oracle has something like this. Just a point for discussion. Thanks, -Brian