I noticed this bug a while ago, but never reported it.
I have noticed that, if you use any capitalization at all when entering a server's address in the Android Subsonic application, the name resolution fails and the server connection does not work.
For example, I sent someone an email with my server name listed as GlennSullivan.Subsonic.org (which works fine in a web browser) and they copy/pasted that into the server address setting on the Droid client and it failed. Once they removed the capital letters it resolved fine.
Please consider either allowing for capital letters (preferably) or automatically down-casing the entry in the Android Settings screen.
Thanks,
Glenn