Tech Info Library file #0021219 details a freeze that can occur if you reset the Power Manager on a PowerBook and have Claris Organizer installed. The problem is due to the fact resetting the Power Manager resets the clock to the wrong date. Adjusting the date will eliminate the problem.
Is your phone battery always at 4 percent?
These battery packs will give your device the extra juice to power through all of those texts and phone calls.