I've ran into this same problem and tried the manual install technique and got it to work. Here are the steps I took:
**warning, I'm not too knowledgeable about OSX's file system, so this may be a bit of a kludge, but it did work**
-Download the "Stand-alone version (all platforms)" from the download section of subsonic.org
-Extract the tar.gz. This will create a folder with the subsonic install files, including subsonic.sh: a script that does the manual installation.
-By default subsonic.sh installs the files to /var/subsonic My computer wouldn't let me install anything there, so I opened subsonic.sh with text edit and changed the first line from "SUBSONIC_HOME=/var/subsonic" to "SUBSONIC_HOME=/Applications/subsonic" so it would live in my applications folder. It might be better to put this somewhere else... but this worked for me.
-Change subsonic.sh to subsonic.command.
-Open terminal and navigate to the directory where subsonic.sh is located. You can do this by running terminal and typing "cd " and then the location listed in the "Where" section when you choose "Get Info" on subsonic.sh
-Type "chmod +x subsonic.command" to make the file executable.
-Double click subsonic.command and it will open a terminal window which will run the script, copy the files to the directory mentioned above... and I think run subsonic.
-Open a web browser and go to
http://localhost:4040 and change your configurations.
That's it! I suspect that you'll need to run that subsonic.command everytime you reboot your computer so that it load subsonic up in the background, but I'm not entirely sure how that works or if it will save your settings you've changed.... or what. I literally just got it working, so just wanted to post this up before I forgot how I did it. I'll update this if I run into more problems or once I figure it out a bit better.
Keebs