I can't send email through my local ISP using my university address, and I can't send email through my university anymore because I don't have a university IP.

The solution I'm looking for is an SMTP server that accepts mail from anywhere (with authentication) and allows users to use whatever From: address they want.

I've spent the last hour looking for a way to do this, playing with Postfix, exim, courier, etc., but can't find it. Perhaps I'm just looking in the wrong place.

You can do smtp Auth with all of those you mentioned.

Courier has support built in for it.

With Postfix you need to use sasl and for exim I have no idea.

Adam

In exim, to accept relaying, you set the

hostlist relay_from_hosts =

line in exim.conf

If you want the address rewritten (sendmail calls this masquerading, I believe), check the

/etc/email-addresses

file.

Don't feel bad that you spent an HOUR working on this without getting anywhere. It took me quite a while to just understand how an MTA works, and what is actually needed to setup a secure SMTP relay. I use Gentoo, so I went with Postfix/Cyrus-SASL because alot of the Gentoo docs use this combo. Here are some links to the docs that I used:

Gentoo Virtual Mailhost Guide
Gentoo Server Project Wiki (currently down, so can't find the exact link)
Postfix SASL Authentication and TLS

The first 2 links aren't too gentoo-centric, so if you're on another distro these would still be good references. The 3rd was written for Postfix 1.x, so it's a little dated... but still good stuff there too. Why don't you give these a look and let us know where you're getting stuck.