I was looking for easy way to do virtual domains so
I downloaded and installed exim 4 cause i heard good things.
After spending several hours understanding how it works,
I finally got my virtual domains working.
However, I think there are others like me who don't know Exim
internals (well, i do now) but know MTAs and might want to do
virtual domains. I put together a tar ball that makes this
easy.
For info, check out
http://samo.org/~chad/exim/
cheers,
chad