All, I've written and now tested a new Handler module, Filter.py, and I've added the various hooks it needs to filter on messages before they are archived.
There are about 70billion different uses for this sort of thing, but the one I'm after is replacing a string (say :1:) with an image tag (say <img src="/icons/green.png">). My two questions are thus:

1. Is there a way to turn off the conversion of < and > to %lt; etc in the archive for a specific list?
2. Where should I submit my patches? They're against a cvs checkout from yesterday afternoon, so likely will patch completely cleanly into the code.

Laurence