mail router and server for adsl gateway

[Micha Feigin <michf@post.tau.ac.il>]

I set up a computer to work as a firewall/router for connecting my local
network to an adsl connection.
I am trying to set up exim to work as a mail router on that machine. i.e
I want it to accept mail from machines on the local network, replace the
from (and possibly reply-to) headers and relay them through an external
smtp connection (not sure yet whether to use the isp's or my uni's
server, which requires ssl authentication).
I was wondering if there is any documentation on how to do this. Maybe
if someone can send me a setup file as an example.
Also is it possible to use a smtp server that requires ssl
authentication as a relay using exim, or is there a more suitable
program for that (is sendmail better for this purpose?)
Also what would be the best way to fetch mail in such a setup
(fetchmail?).
And lastly, are there any recommendations for a pop3 or imap (preferably
both as I want pop3 for one user and imap for the other) server to use
in such a setup (I need a small one for 2 users).

Thanx

-- 
Micha Feigin
michf@math.tau.ac.il