The iPhone Dev-Team has updated RedSn0w to resolve a problem with MobileSubstrate that occurred when rerunning the jailbreak.
The b3 version of redsn0w fixes a problem where re-running redsn0w over an existing jailbreak would cause MobileSubstrate-based apps to stop running until MS was installed again. Now you can re-run the redsn0w jailbreak step without worrying about that (but still remember to de-select the "Install Cydia" option if it's already installed).
You can download the latest version of redsn0w from here.
You can find instructions on how to use redsn0w to perform an untethered jailbreak using the iClarified Jailbreak Wizard.
The b3 version of redsn0w fixes a problem where re-running redsn0w over an existing jailbreak would cause MobileSubstrate-based apps to stop running until MS was installed again. Now you can re-run the redsn0w jailbreak step without worrying about that (but still remember to de-select the "Install Cydia" option if it's already installed).
You can download the latest version of redsn0w from here.
You can find instructions on how to use redsn0w to perform an untethered jailbreak using the iClarified Jailbreak Wizard.