Cingular's popular, consumer smartphone, the BlackJack, has suffered from short battery life since its inception--hence the inclusion of two batteries in the original model. Recent BlackJack buyers found that their phone comes with one standard and one extended life battery. Those BlackJackers that got in on the handset early are eligible for a free extended life battery from the carrier: Handsets with IMEIs between 352794010030189 and 352794012269959 are eligible.

For more on BlackJack's battery snafu:
- see this post from Brighthand