Problem: Sticky key, keyboard and/or trackball does not work properly and battery drains...

Symptom: My Curve 8310 shortcuts would not work (alt+(left shift)+h = help), alt+(right shift)+del = reboot) and I could not press alt or either shift simultaneously. The trackball button would stay depressed without being touched.

Cause: sticking button. If a button is already pressed, it will over ride the ability to simultaneously press other buttons and may cause battery drain.

Resolution: clean the phone. Carefully take phone completely apart and clean lint/dust inside out.

Fixed!!!

And don't carry it in your pocket. Use the pouch that came with it!