[Zope] Problem with Roles & Management screen.

Hi! I've been trying to define a staff role, which is basically a Manager that can create/edit/delete 2 kinds of objects (OrderedFolder, Structured Document). Now I'm getting a funny behaviour: My test user can access the "/manage" Frameset, but instead of the contents pane, the user gets the website rendered. (The frameset contains the link to manage_workspace, but this seems to be redirected to index_html :( ) So which permission do I need to set, that the "staff" role may really see the management screens? Additionally it seems, that there are "Add Structured Document" permissions, but no "Change Structured Document" permission :( Andreas