Easy to setup smtp server/daemon?

[vespaman]

I'm doing some development of an embedded firmware that sends mail to a smtp server when trouble. Now, I need to test this thing, and need to install some smtp server on my gentoo box.

I guess qmail and postfix will do the trick, but which is the more easy to set up? I only really need smtp, maybe there are any other smtp server software even more easily maintained.

Any pointers or suggestions appreciated,

Micael