[Zope] python script parameters

[Ben Avery]

hi,

I'm having problems with passing a number of parameters to a python 
script called by XML-RPC.
I want some of the parameters to be optional, and passed as empty 
strings. I have tried to do this by setting default values as empty 
quoted strings. But playing around even with setting non-empty default 
values in a list of params doesn't seem to work.

e.g.
if I set the parameter list of the method as: a, b="aardvark"
and then test the script, if I leave b empty, the default aardvark is 
assumed.

but if I switch the order round, and set the param list as: b="aardvark", a
and do the same, the script breaks with the error 'the parameter b was 
ommited from request.

could anyone tell me how I do this: i.e. have a parameter list with some 
values set with defaults, not just the last one?

TIA

Ben Avery
YouthNet UK
www.thesite.org