I must admit to not understanding why this should only break over xmlrpc and not directly from Zope. The problem appears to be that my method is defined something like:
def method(self, *args, **kw)
mapply doesn't put things into **kw arguments of methods. I wanted this once for a product in Zope 3, looked deeply into mapply, and talked to Jim Fulton about it. IIRC, Jim said that mapply shouldn't put things into **kw arguments because it isn't at all explicit, and would end up implicitly putting in a whole bunch of things that you generally wouldn't want in a lot of cases. Can you make up a simple python module to demonstrate your case, just using a method, and mapply? It may be that there's a way to achieve what you want, while still keeping things reasonably explicit. -- Steve Alexander