[Zope] Adding ZClasses

I'm attempting to allow my users to add zclasses. I always run into the same problem. The following code is in a method in a folder (a Yihaw folder in this case). <dtml-with "manage_addProduct['YihawDirectory']"> <dtml-var YihawChannel_addForm> </dtml-with> I get the form to come up but when I post it I get a "Resource not found" error. All I want to to is leverage the forms that already exist in the products folder. What am I missing? thanks, -mjm