[Exim] usage of mail. & smtp.

I have a machine with a real name & IP to which I also
alias mail.machine.name (and IP)
and smtp.machine.name (and IP).

All my users reference mail.machine.name for BOTH smtp & pop3 services.
Is there any 'requirement' to have an 'smtp.machine.name' when my DNS
points only to 'mail.machine.name' ?

Can I safely remove my name & IP for smtp.machine.name ?

--
Jim Pazarena    mailto:paz@qcislands.net
                http://www.qcislands.net/paz