I would love to see this work but when I managed to get it to run it just said it could not connect to the server and could not find my sound card (alsa), though it does claim to support alsa.
I also tried squeezeslave but it appears this does not support alsa at all.
I found a mention of something called slimslave here:http://forums.slimdevices.com/archive/index.php/t-3831.html
However although the post says to scan that forum for info I cannot really find any more info anywhere on the web which is of any use. Perhaps slimslave does not exist??
At any rate it would be great to have something you could run on an MD for mutli room audio. The current music player is simply useless... (it doesn't appear you can sort by album, or create smart playlists, or do any of the thinsg which make players like iTunes to useable).