For some time he releases an upgraded version of ultrasn0w 1.2.4 in Cydia that is compatible with the new iOS 5.
Specifically, the new ultrasn0w supports the following baseband:
- iPhone 3G and iPhone 3GS: 04.26.08, 05.11.07, 05.12.01, 05.13.04, 06.15.00
- iPhone 4: 01.59.00
This publication is aimed at those who need to do unlock the device and for anyone else. If you want, then, go to the new iOS 5 and keep the unlock should keep and baseband. This is done by creating a custom ipsw using the new redsn0w (currently for Mac only)
Be aware, however, that the jailbreak so far is tethered (excluding holders of old-bootrom iPhone 3GS) and you should connect your iPhone to your computer whenever you want to reboot.
Beware, however: Users iPhone 3GS with baseband 06.15 must install the new iOS 5 to disable Location Services. You can reactivate later, but the first time will be prompted to disable it!
Also, if you accidentally used original ipsw to upgrade to iOS 5 you need to reflash the baseband to 06.15 again through redsn0w. And remember in the future to never use original ipsw!
Again: This publication is for users with unlocked iPhone using ultrasn0w. The others just ignore it!