You can get Palm Desktop to work in Panther by logging in as root and doing a fresh install. Make sure you have the the latest iSync Palm conduit installed too, and iSync will work with your Palm. This hint came from the Palm Brighthand Forums.
[robg adds: I had no problems with Palm HotSync via Bluetooth on my PowerBook, but I know others have had issues...]
Mac OS X Hints
http://hints.macworld.com/article.php?story=20031029195823894