Domain-style address on 7300

[Bob Clements]

I've just gone through the process of getting my Unix-pc site
properly registered with a real domain name and getting an
internet neighbor to be a mail exchanger.
("k1bc" --> "k1bc.lex.ma.us")
It's still connected just via uucp, of course.

Would anyone who has gone through this be willing to
advise me as to what mail software I should be running
on the 7300 and what configuration there is to go through?
I guess I can bumble my way through it, but if you've
done it recently enough to remember the details, I'd
appreciate some email (to my work address -- clements at bbn.com).

Thanks,
/Rcc