> I wonder if we should ship our sendmail.cf with some anti spam
> stuff enabled At least this 8.8.8 that came with 1.3.3/sparc
> seems to be wide open ..
>
> We should perhaps deny relaying and perhaps also accepting mail
> from hosts that have no valid mx or such.

I think this is a good idea.

We should at a minimum not ship a sendmail.cf which makes
sendmail wide open for relay abuse.  I don't know whether there
should also be some file/database where you could add hosts
and/or subnets from where you permit relaying, so that POP/IMAP
users could use the SMTP port for message submission.

As for the "require valid mail delivery DNS lookup for originator
address", that might also be a good idea, since if mail delivery
should fail sendmail is under obligation to send an error message
back.  However, it tends to slow down message delivery (OK, ident
is probably a worse offender in that regard ;-).

- H=E5vard