[Zope] Feature request for metal - default macros?

[KevinL]

Heya,

Quick question:  Is there a good way to set a "default" macro?  What I'm
trying to do is setup a situation where we call:

here/blah/skins/helpfile/macros/?language

Where ?language resolves to the current language in use.  What I want to
do is say "if the language selected doesn't exist, use english" - or,
from the macro side, "if the macro specified does not exist, use this
macro instead".

Is that doable easily?  Is it something that could be included as a
feature in metal?

(I know there's probably other ways to do languages specifically, but I
thought the feature itself may be useful generically.  And we're doing
languages this way because we're giving clients cvs access to the skins
dir, and it's a nice easy way to say "if you want to change this block
of text on this page, edit this file", without descending into ZMI
stuff.)

KevinL