Alongside, Redsn0w 0.9.10b1 the iPhone Dev Team has also released PwnageTool 5.0.1 untethered iOS 5.0.1 jailbreak update, which is available for Mac users.
See also:
Download iOS 5.0.1
Redsn0w 0.9.10b1 Untethered iOS 5.0.1 Jailbreak
Untethered Jailbreak of iOS 5.0.1 with Redsn0w 0.9.10b1 (Windows/Mac)
People wo do not know, PwnageTool let you allow to create a custom IPSW which also preserves your iPhone’s baseband to perform unlock with UltraSnow and Gevey SIM.
As PwnageTool is specific for Mac, so Windows users can create custom firmware through RedSn0w and Sn0wbreeze.
Download PwnageTool 5.0.1 for Mac