outgoing mail address for mutt

[lowell]

Folks,
        I've gotten fetchmail to collect from my pop mail account at 
roadrunner, and mutt to show me the messages, but whenever I try to mail 
out or reply it names me lowell at localhost.localdomain.
        Where can I set my address so mutt can find it? I tried it at 
the top of muttrc, but that didn't work. I'v also tried mail to send 
with and mutt receives the same bounced message w/ it...