redsn0w 0.9.5b4Redsn0w has just been updated to beta 4 to support the latest iPhone OS 4 Beta 4 firmware.

iPhone OS 4 Beta 4 was released by Apple last week, which since Beta 2 has closed the jailbreak loophole used by Redsn0w 0.9.5b1 and b2 to jailbreak OS 4.

But with this latest version of redsn0w, you should be able to jailbreak iPhone OS 4 again on iPhone 3G.

redsn0w 0.9.5b4

An excerpt from iPhone Dev-Team on this release is as follows.

This is a beta release of redsn0w targeted at developers of jailbroken apps. It uses the same pwnage2 DFU-mode exploit that we’ve been using since the 2.x days. Nothing new is revealed to Apple, and it’s not applicable to the iPad. Don’t go near it if you use yellowsn0w, ultrasn0w, or blacksn0w.

YOU SHOULD STAY CLEAR OF THIS BETA SOFTWARE IF YOU RELY ON A CARRIER UNLOCK. That’s because the beta redsn0w works only if your device has already been upgraded to the stock 4.0beta1/beta4 IPSW from Apple, which contains a baseband update. If you installed that IPSW, you’ve already lost the carrier unlock until the next planned release of ultrasn0w and blacksn0w.

Here are a few points to note if you are a developer of jailbroken iPhone apps:

  • The latest Redsn0w jailbreak tool is only works on iPhone 3G.
  • This beta version does not perform hactivation. Users will require an Apple UDID to get past the activation screen.
  • Redsn0w 0.9.5 beta 4 works only on Mac OS X and does not have a Windows version of the software.
  • Do NOT use Redsn0w if you have unlocked your iPhone. This is because iPhone OS 4.0 beta 4 contains a baseband update, which cannot be software unlocked currently. 

Instructions to jailbreak iPhone 3G on iPhone OS 4 Beta 4 using Redsn0w 0.9.5b4 are exactly similar to the last release. Please read all the instructions posted here carefully before upgrading your phone to iPhone OS 4 Beta.

Download Redsn0w 0.9.5b4 for Mac

If you are on iPhone OS 3.1.3, you can follow our step by step guides to jailbreak iPhone 3GS with Spirit here, iPod touch 3G untethered here, and iPad on OS 3.2 here.

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