i sync my tx with bluetooth (since 10.4) and have NEVER used the usb cable.
it is a major pain to setup (set it up in iSync, be sure to select palm syncing there); setup a bluetooth connection on the palm itself (pair it in the bluetooth pane in system prefs)
u need palm desktop installed first tho (and, btw, the place i keep my memos stored). you need to do some maneuvering with hotsync options...
wish i could be more specific, but spent half a day fiddling with this; it DOES work tho, i have the tx working with Address Book and iCal...
google a bit, might better info out there; it IS do-able....