I've had an unlocked Palm 680 for about 5 months now, and it ran flawlessly up until 3 or so days ago.

I unplugged it from the wall charger and the charging indicator icon and the green light remained on. It showed battery life at 100% for a few hours and then dropped immediately to 0% (icon and red light remained on), after which it shutdown in 30 or so minutes.

The same thing has been happening for the past few days. My roommate has the same phone, and I tried his battery. The icon and light were there, and the battery showed 37% or something... I've also noticed that the battery gets very hot upon charging.

Any help would be much appreciated.
Thanks.