Actually, I don’t have it set up as a feed. You can just download it, move it to the slug and do “ipkg install /path/to/ipkg”.
Another thing you can do is grab the package straight from the web, like:
[email protected]:~# wget http://nightlies.mt-daapd.org/mt-daapd_svn-1005-1_armeb.ipk
[email protected]:~# ipkg install ./mt-daapd_svn-1005-1_armeb.ipk
Might be easiest to just let it install the new config file, as well — it’s got all the new options and whatnot in it.