GreenPois0n RC5 for Windows is just released by Chronic Dev Team to untethered iOS 4.2.1 jailbreak iPhone 4, iPhone 3GS, iPod touch 4G, iPod touch3G and iPad running on iOS 4.2.1. GreenPois0n RC5 for windows also does not require SHSH blobs for iOS 4.2b3 like the Mac version which was released 2 days back.
GreenPois0n RC5 for Windows will also be sporting feature animated custom boot logos . You can check the video of the custom boot logo and here are the steps by which you can enable /disable animated custom boot logos.
We are working on to release the instructions to untethered jailbreak your idevice with GreenPois0n RC5 for Windows. If you are on Mac below is the download links and guide to untether jailbreak iOS 4.2.1 on iPhone, iPad and iPod touch. iPhone 4 users with old baseband can also unlock their iPhone 4 after restoring with the guide given below. Join us on twitter or facebook fanpage for immediate updates on the upcoming unlock.