[Zope] How do I get an owner of an object?

I'm creating some kind of CMF and I need to test if a user is owner of an object, in order to let him edit or not the object. The regular: AUTHENTICATED_USER.has_role('Owner', this()) is not working fine since it's based on acquisition: if you own a folder, it presumes you own the things inside it. So I tried owner_info, like zope uses, but an user has to have 'View management screens' to call it. I don't want to give this permission to most of the contributors. Is there an work-arround? Thanks, Miruna