The iPhone dev team have released RedSn0w 0.9.6 beta 1 for Windows to jailbreak iOS 4.1 on iPhone 3G and iPod Touch 2G. If your iPhone 3G relies on Ultrasn0w unlock, stay away from this Redsn0w release, as it updates your baseband to the latest version, making it impossible to unlock (for now).
Redsn0w 0.9.6 can also jailbreak iOS 4.2 on iPhone 3G and iPod touch 2G, but that comes with a high risk warning.
This is a beta release of redsn0w for the iPhone3G and iPod Touch 2G at FW 4.1 or 4.0. It uses the same pwnage2 DFU-mode exploit that we’ve been using since the 2.x days. It does not include the SHAtter exploit developed by pod2g. Nothing new is revealed to Apple with this jailbreak.
if you have an “MC” model of the ipt2g, your jailbreak will be tethered…sorry! (Consider rolling back to a FW supported by jailbreakme.com or spiritjb.com)
Guide to Jailbreak iOS 4.1 on iPhone 3G/iPod Touch 2G on Windows
The instructions to jailbreak iPhone 3G and/or iPod Touch 2G with iOS 4.1 on Windows remains exactly same to what we had written for Mac version. Anyway, here is a brief guide to help you with the same.
1. Download iOS 4.1 for iPhone 3G & iPod Touch 2G
2. Download iTunes 10
3. Download Redsn0w 0.9.6b1 [Mirror]
4. Manually update your iPhone 3G or iPod Touch 2G to iOS 4.1
5. Start Redsn0w 0.9.6B1. Click on Browse button and select iPhone 3G 4.1 firmware downloaded in step 1.
6. Now click next and Redsn0w 0.9.6b1 will prepare data for jailbreak.
7. Now select “Install Cydia” and click Next.
8. Power off your iPhone 3G and connect it to computer, only then click on next button of Redsn0w 0.9.6b1
9. At this stage you will need to put your iPhone in DFU mode, to do this hold “Power” button and then while holding the “Power” button, you will now have to hold “Home” button too for about 10 seconds. Now after few seconds release “Power” button but keep holding “Home” button until installation begins
10. Now just wait until Redsn0w completes the rest of the process. Once done, your iPhone 3G will restart automatically and you will find it jailbroken with iOS 4.1.