yes, sendmail should be up and running automatically .... be sure to
enable to access list which would connect other than localhost ...

configure SMTP accesslist as documented on
http://www.sendmail.org/~ca/email/auth.html

and you should see the documentation on mail relay ..

# by default we allow relaying from localhost...
localhost.localdomain RELAY
localhost RELAY
127.0.0.1 RELAY

hth

raqueeb hassan
congo