The iPhone Dev Team has today released the updated version of redsn0w - redsn0w 0.9.10b4 which includes @xvolks's iBooks fix merged into @pod2g's untethered jailbreak. The Cydia package for untethered iOS 5.0.1 jailbreak called - Corona has also been updated to include this fix. This updated untethered jailbreak will also fix "launchctl" issues.
If you are not on iOS 5.0.1 yet and wish to upgrade to iOS 5.0.1, follow this tutorial. It describes how to upgrade to iOS 5.0.1 while preserving baseband, jailbreak, activate and unlock your iPhone.
To update your current iOS 5.0.1 untethered jailbreak using redsn0w, just download the latest redsn0w 0.9.10b4 (download for Windows, download for Mac OS X) and run it. Click jailbreak. Then follow the onscreen instuctions and when you see the options, de-select "Install Cydia" option and click Next.
Example picture.
To updated your current iOS 5.0.1 untethered jailbreak using Corona package in Cydia, just open Cydia, let it update database, and search for Corona. Install Corona 5.0.1 Untether package and reboot your iDevice.
Example picture. Credit - Chronic Dev team
You can use any of the above described methods no matter which method (redsn0w or Corona) you used before to have iOS 5.0.1 untethered jailbreak.