[Exim] exim - sendmail problem

I have switched to Debian 2.2.r2 and am trying to use exim as my MTA.
However, when I try to send from Mutt or Pine, I get an error which
indicates that my sendmail.cf is not present. Of course, exim cannot
co-exist with sendmail. But I can't find any helpful doc to help me out
of my dilemma. Anyone with some specific ideas? (Using minicom for
sending is a bit primitive)

Thanks,
sam