These are instructions on how to jailbreak your iPhone 3GS on the 4.3.1 firmware using RedSn0w for Windows.

Make sure not to update to iOS 4.3.1 if you need an unlock as one is not yet available unless you opt to use the iPad baseband.

IMPORTANT FOR UNLOCKERS
During this process you can update your baseband to the 06.15 version. If you are on 05.14 or 05.15 or higher you will need to do this to unlock. You do not need to do this for jailbreak only. Please read the following very carefully before deciding whether to do this.
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Apple has removed its built in methods to help developers detect jailbroken devices from iOS 4.2, according to NetworkWorld.

This detection API let the MDM applications in effect ask the operating system if it had been compromised. Jailbreak exploits typically change a number of operating system files, and exploit one or another low-level OS features to let users directly load their own or third-party applications.

Previously, developers had created their own series of operating system checks to detect jailbreak.
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Backgrounder by Lance Fetters (ashikase) has been updated to support iOS 4.2.1

Backgrounder allows for total control of backgrounding on an iPhone/iOS-based device. With Backgrounder, *you* decide when an app should keep running, and when it should quit.
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These are instructions on how to watch Flash video on your iPhone, iPad, or iPod touch using the iOSFlashVideo bookmarklet. Currently support sites are Dailymotion, Flickr Video, MegaVideo, Vimeo.

1 – Press to launch Safari from your SpringBoard.
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