Segui o tutorial abaixo.. estavam com o 3.1.2.. funcionou tudo redondo
notei um consumo exagerado de bateria hoje... alguem mais?
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Jailbreak iPhone 3GS iOS 4 GM with PwnageTool
STEP 1 – Required Stuff
* Download PwnageTool 3.1.5
* Download PwnageTool Bundle for iPhone 3Gs iOS 4 GM [Mirror 1]
* Download RedSn0w 0.9.5b4
* Download iOS 4 GM
STEP 2 – Add Custom Bundles to PwnageTool
1. Extract the downloaded iPhone2,1_4.0_8A293_bundle.zip.
2. Right Click on the PwnageTool.app and click on Show Package Contents.
3. Then navigate to the following directory: Contents>Resources>FirmwareBundles and copy the extracted iPhone2,1_4.0_8A293_bundle.bundle into FirmwareBundles directory.
STEP 3 – Add New Cydia to PwnageTool
1. Right click on the downloaded RedSn0w jailbreak and go to Show Package Contents.
2. Go to: Contents>MacOS and copy the Cydia.tar.gz from that folder to your desktop and Extract it.
Now copy the extracted Cydia folder to PwnageTool.app. To do that:
1. Right click on Pwnagetool.app and ‘Show Package Contents’.
2. Go to : Contents > Resources > CustomPackages and then Right click on ‘CydiaInstaller.bundle’ and ‘Show Package Contents’
3. Go to: Files folder and overwrite all the files with the ones you just extracted from redsn0w. That’s it.
STEP 4 – Create Custom iOS 4 Firmware
Now that you have modified the PwnageTool.app, it’s time to create custom iOS 4 firmware with pwnageTool for iPhone 3GS using downloaded iOS 4 GM. If you don’t know how to, follow the guide linked below to create Custom firmware with pwnageTool,
How to: Create Custom Firmware with PwnageTool
STEP 5. Restore Custom Firmware
Once you’ve created the custom firmware (CFW), Put your iPhone 3Gs into Recovery/Restore Mode and restore your device via iTunes with CFW. That’s it.
Have fun with iPhone 3G iOS 4 jailbroken!