Those who are new to this, recently iPhone-Dev Team and Chronic Dev Team released iOS 5.0.1 Untethered jailbreak for A4 devices which includes iPad (FirstGeneration), iPod Touch 4G, iPod Touch 3G, iPhone 3GS, iPhone 4. Users who are using non jailbroken device running 5.0.1 firmware can use RedSn0w whereas those who are already using tethered jailbroken device running iOS 5.0.1 can make it Untethered by installing a small tweak called Corona 5.0.1 Untether.
However, after performing jailbreak users started facing problems with some specific application which are actually crashing if you try to launch them and also redirecting you back to your Springboard. Now in order to resolve this iBooks issue iPhone-Dev Team has released redsn0w 0.9.10b4 and Chronic Dev Team has updated Corona 5.0.1 Untether version upto 1.0-5.
From iPhone-Dev Team:
Update #4: The b4 version of redsn0w incorporates the 5.0.1 fix for iBooks, and also for sporadic problems with launchctl. Thanks to @xvolks for merging the iBooks (sandbox) fix from @comex’s github into the overall corona untether from @pod2g! As usual, you can choose to install the fix either by re-running redsn0w over your existing jailbreak (de-select Cydia if you do that), or by installing the corona package from Cydia (it’s the same set of files no matter which way you choose).TIP: If auto-detection fails and redsn0w tells you no identifying data was found, you can always pre-select the appropriate 5.0.1 IPSW using “Extras->Select IPSW”.
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