My Dell axim x30 won't turn on/off.

My Dell axim x30 need recharging after two days. After a few hours on house power the display operated very slowly. I continued charging using the car's adaptor for about six hours. I've switched back to house power after the trip and the on/off button is flashing continuously. I can't turn it off. I've had problems with the on/off switch during and after recharging and have managed to get the unit into operation.