[Zope] Developing External Methods

[victor@idaccr.org]

I've just installed Zope, and as an initial test I entered the various
files from the "Job Board" example given in a "Technical Introduction
to Object Publishing with Zope".  However, when I try to "Add External
Method", I get the error "Error Type: AttributeError Error Value:
func_defaults" with no line number given.  I really can't see what the
error is.  I haven't really tried staring at the locations of the
traceback in the Zope functions, but should this really be necessary?! 
So this brings up the general question: when you're writing new
External Methods, what development methodology do you use?  Unless
you're perfect (and I'm not one of these) and never make any errors,
you certainly need something which will get the methods, debugged, etc.

Also, I also tried, the alternative suggested in the "Zope Content
Managers Guide" of putting the external methods in the Extensions
subdirectory of a Product (I made a new product called "Test"), but
even though I gave Test.JobBoard as the name of the module file, it
couldn't be found.

           Victor