T-Mobile has new BlackBerry 8100 Pearl software v4.2.1.107

Redesigned Application list that is displayed when you press the Menu key from the Home screen.
Improved quality and reliability of the audio experience during phone calls
Improved two-way audio experience
Ability to use t-zones browser and Picture Messaging for all customers (additional charges may apply)
Improved persistence of Call Logs and Messages
Improved consistent behavior of the ABC indicator
Improved stability when using a Bluetooth headset
Improved reliability of myFaves icon appearance
Improved reliability of keyboard lock feature
Daylight Savings Time Patch Integration