LinuxQuestions.org - Configure sendmail to *use* authenticated SNMP relay?

I've seen lots of docs about setting up sendmail to be an SMTP relay.

I would like to configure sendmail to use an autheitcated smtp gateway to send mail from, where a legitimate account exists for sending logwatches, etc.

So...2 questions:

1) how can I force sendmail to use a remote snmtp server as a rellay and authenticate.

2) how can i force all mail to se sent from one address? (ie. monitor@domain.com)

the server will not hold user's which will be emailing and such, but i'd like all email coming to root forwarded (which i can do) but i need it all to come from one legitimate address.