There is a new video going around in the wild which shows iPhone 3GS (with new bootrom) on iOS 4 jaibroken using an upcoming version of Sn0wbreeze. This video has been confirmed by iH8sn0w – the developer behind popular iPhone jailbreak tools such as sn0wbreeze for iPhone 3.1.3 / 4.0, f0recast and BlackBreeze as legit. Unfortunately though, there is a little catch to it. 1) it is a tethered jailbreak (whenever you turn off your phone, you will need to re-connect it to a computer to be able to turn it back on) and 2) it will only work for those devices which have their SHSH blobs (ECID SHSH) files for 3.1.2 (NOT 3.1.3) saved on Cydia. This jailbreak also required a special tool for rebooting as shown in the video below.
There is no ETA (Estimated Time of Arrival) on the release. According to iH8sn0w, he will “see if [he] can produce a tool that will do this job…”.
Oh and here is the video which shows iPhone 3GS (new bootrom) jailbroken on iOS 4.
