Battery light flashing but battery isn't dead

The battery light on my Dell Latitude is flashing in the orange/green sequence that usually indicates a dead battery. The lights on the battery itself also flash when the button is pressed to indicate the power level. However, the battery holds a charge just fine and lasts around two hours. Strangely though it dies about half way through and thinks its dead, but the machine can be restarted and the machine runs for another hour with a 0% indicator in Windows. Is there any way to reset the battery gauge?

 

i have almost same problem, my D420 battery holds for about 2h, and after that battery LED blinks(Vista shows ~5min left) and system hibernates,
after I turn on my D420 again, battery holds for Extra ~30min, unless Vista shows 5mins left, and that 5mins decrease very slowely.....later show 4...3...2...1...also 0 and @0 holds for 5..10minits....

i found BATRCAL utility from dell forums, but it is for The Latitude LM & LM/mmx and Inspiron 3000/3200 notebooks

somebody have tried the utility on newest notebooks and under Vista?

 

Flashing battery indicator does not always spell problems with the battery.

Flashing power indicator and screen blackout are also signs of hardware components (not necessarily the battery) that do not function properly. For example, if your RAM is not properly set, then the battery indicator flashes.

Just to be 100% sure it is a battery problem, try using the laptop without or with the battery while plugged into an outlet and see if you can keep it on for say 3 hours without the screen blacking out and battery indicator flashing.