iPhone-dev team has released the updated version of Ultrasn0w iOS 5 Unlock which makes it compatible to iOS 5 which was released by Apple just few days back. This update is just for existing Ultrasnow users who already have applied ultrasnow to their devices. This update doesnt even add any new baseband to the existing list of supported basebands. This update is required for any ultrasn0w unlockers who want to try out iOS5.
The supported basebands for the iPhone 3G and 3GS are 04.26.08, 05.11.07, 05.12.01, 05.13.04, and 06.15.00. The baseband supported for the iPhone4 is 01.59.00.
For those of you who doesnt know the difference between Redsnow and ultrasnow, here it is. Both these tools do two different jobs. While Redsnow jailbreaks your iOS Apple device, ultrasnow unlocks your iOS Apple device. (that’s what I know so far.)
The blog post adds that existing ultrasn0w users who want to try iOS5 right now must be having old-bootrom iPhone3GS devices and they already have an untethered jailbreak via redsn0w and for everyone else, the iOS5 jailbreak is currently tethered.
Developers even warn users of iPhone3GS owners with baseband 06.15 to “Disable Location Services” during the setup. As usual, unlockers are advised to steer clear of stock iOS 5 IPSWs. Updating will also update their baseband, which may or may not be available to unlock with ultrasn0w in the future.
“Unlockers should never go near stock IPSWs,” says the team.
Also, the only way to get to iOS5 while preserving ultrasn0w-compatible baseband is by using a custom IPSW which can be created using redsn0w. Version of the Redsnow which must be used for creating a custom IPSW must be 0.9.9b4 or higher (The version 0.9.9b5 is right now only available for Mac only and Windows version is still awaited), which is available here.
Via : iPhone-Dev Blog