[COLUG] sendmail question?

[Dave Reed]

At work they switched to a new mail server (running MS exchange I
think). We still have Sun Solaris machines running sendmail. When a
message is sent to dreed at capital.edu it goes through the new mail
server and is delivered correctly, but when it is sent to just dreed,
sendmail delivers it locally to /var/mail/dreed.

The sysadmin is not a sendmail expert (nor a member of this list) but
I told him I'd ask if anyone knew how to configure sendmail to always
use a separate mailserver. He mentioned something about a "dumb" or
"null" setting but google hasn't found the answer for him yet.

Can anyone help?

Thanks,
Dave