[Zope] Propertymanager

Hi there... I'd like to create a ZClass, which is supposed to have the behavior of both, Objectmanager and Propertymanager but I don't want it to inherit from the Folder class. The Problem is once I create a new ZClass in my Product I can choose ZClasses: Objectmanager as a baseclass but I can't choose Propertymanager as a base class. Is there any way to aviod this problem? Thank a lot Falk Eilenberger