In short, and I haven't verified it in a test case, if your ZClass inherits from both ZClasses and from regular python classes, the python classes must be first, or you won't be able to access the python classes methods. Instead you might get a "missing doc string" error, or perhaps some other error. I need to try this with a simpler test case, but simply changing the order of inheritance in my ZClass so python classes were first solved my problem. And yes, all my functions had doc strings and yes, the methods that didn't work originally were only defined in the python classes. What I tried, proof of my claim: CatalogAware python class -> Workflow python class -> ZWorkflow ZClass ObjectManager python class -> OrderedObjectManager python class (mine) -> Foodbase pytohn class and then Food inherited from ZWorkflow and FoodBase. This didn't work. ****** But inheriting directly from just Workflow and FoodBase did work - ******* ******* wrapping Workflow in a ZClass is what caused my problem ******* Inheritng directly from Workflow, then from a new plain-vanilla ZClass I created and then from FoodBase didn't work. So I change the order: Inheriting from Workflow, then FoodBase (both python classes), then from the ZClass solved the problem! -- Itamar S.T. itamars@ibm.net