My Google searches are producing a large number of hits.  As I continue
to wade through them, I think I'll query the great minds here.

I have a Linux server that needs to send email.  The "relay" server
requires:

- Connection via SMTP.
- Connection to a non-standard port number
- Authentication as a valid email account user

1. I have found various documentation of how to configure my Sendmail
server to *listen* on a port other than 25 but not where I can tell it
to *send* on a different port.  Where do I configure it to relay to a
port other than 25?

2. The authentication options are confusing to me, so far.  I continue
to read but if someone has a good, clear resource for Sendmail
authentication as a user on another SMTP server, I'd appreciate a
pointer to it.

That second question is a little vague.  I'll read more so I can ask it
better later.

Alan