i would suggest finding a slightly intoxicated female before it goes dead...
but seriously.. what color is the sticker in the battery case?
did your dad get it wet slightly? read this thread:
http://www.blackberryforums.com/showthread.php?t=14213
its the exact problem you are having...
THE FOLLOWING SUGGESTION IS JUST THAT... A SUGGESTION. DONT CRY IF YOU FUBAR THE THING.
in the past, i have had several electronic devices suffer from water damage. they have ranged from TI-83s to TV remotes and car audio face plates...
the moment i realize the unit(whatever it is) has suffered water damage, i remove the battery if its available. dry the unit as best you can with a small lint free cloth. if the device can be dismantled without a problem, do so.
i have a gas oven.. the pilot light keeps the oven at about 140 degrees, and relativly no humidity.. place the item in your gas oven if oyu have it. if not, a hair drier could be used also... i leave the gadgets in over night, and the next day replace the battery and see if it flys.
7 times outta 10, the things work again. its obvious that the motor is shorting out due to something.. the fact that it begins to vibrate before the system POSTs (do blackberries post? you know what i mean, right?) is a clue that the vibrations arent due to an OS issue. if your feeling lucky, open it up and remove it or check the contacts. if you think about it, tmo aint gonna replace it if its water damage anyways (unless oyu have that plan) so you have nothing to loose. i would rip that little motor out and be happy with my new vibration free 7290.