[Zope] Inheriting CatalogAware?

Hi, I have one question. I have a Class, say, BaseClass which is a subclass of CatalogAware and ObjectManager (in that order). I have a second class which is a subclass of BlaseClass. SecondClass should be fully CatalogAware, yes? Just have to know because if it is, my error lies elsewhere..... ;-) Thanks in advance, Nils