[exim] LF: simple localhost relay only config

Hello everyone,

It's been a while since I really played with Exim and I'm trying to make up a
new config for a relay-only system. It's for a web server that needs to be
able to send out email directly (rather than using something like ssmtp to
relay to a MTA for delivery), but is only for use by processes on the server
itself.

I know the config should be relatively simple and I've taken a config from my
full-fledged MTA and started pruning, though I was hoping to get a few configs
from other people to check to make sure I haven't missed anything. I am also
left asking myself the question... in this particular setup, is it common for
it to run as an SMTP daemon, or is it usually set up to only take email in via
"sendmail" pipe?

Anyways, if any of you out there have simple configs used on your web servers
for sending out email only, I would really like to get a peek at it.

Eli.