Unfortunately, on iOS 4.3.1 ultrasn0w has certain functionality problems and those who updated were left without the possibility to unlock iPhone terminals. Yesterday there was one unofficial patch in Cydia, which for some solved the problem, but the Dev Team is "moving quickly" to solve the situation and Musclenerd announced last night that he managed to solve the compatibility problems between ultrasn0w and iOS 4.3.1. Unfortunately, the team still needs a few days of testing to make sure everything works correctly on multiple devices, so the new version of ultrasn0w will be available in Cydia in the next few days.
The new version of ultrasn0w DOES NOT UNLOCK only for the old basebands. We are not talking about a new unlock solution, but about solving compatibility problems with iOS 4.3.1.
