sorting/filtering while 'inc'ing new messages?

[pd]

I'm familiar with the .maildelivery system, but that's designed for
use on a machine that works as an smtp server and receives messages
into spool files.

I'm running nmh 1.3 on a Mac running OS X (Leopard), and I'm fetching
messages from a POP3 server. I'd like to be able to do spam
filtering, and to sort messages into different folders when I do the
'inc'.

Any mechanisms for doing that? I haven't found anything yet.

Ideally, I'd like to be able to run arbitrary commands or scripts on
each new message that's inc'ed, so I can do some automatic processing
on certain messages.

Thanks!

-pd

[pd]

Well, I wound up writing my own Perl script to go through all the
messages in +inbox, and process them with filters in a separate file.
This file has a format similar to .maildelivery, so you can specify a
command for each match, such as "refile ...", etc. Messages not
matched by any filter get refiled into +misc, so +inbox is just for
unsorted messages. I'm still tweaking this, but it seems to be
working in general.

-pd