Other than that small little detail, jailbreaking iOS 5.0.1 with RedSn0w is a cinch…
How to jailbreak iOS 5.0.1 beta
Step 1: Download iOS 5.0.1 (developers) and ensure you have the public iOS 5.0 available as well. You can grab iOS 5.0 from our downloads page.
Step 2: Open RedSn0w 0.9.9b7 (download here) and select Extras > Specify Firmware > and point it to the iOS 5.0 firmware. It should identify the 5.0 firmware without error.
Step 3: Go back to the main screen of RedSn0w and place your device into DFU mode. Click Jailbreak, and then select Install Cydia.
Step 4: Your device should jailbreak, but your Cydia icon will be white due to it being a tethered jailbreak. Place your device back into DFU mode.
Step 5: Again, from RedSn0w’s main page, select Extras > Specify Firmware > and point it to the iOS 5.0 firmware. It should identify the 5.0 firmware without error.
Step 6: Select “Just Boot” from RedSn0w’s Extras menu, and it should perform a tethered boot on your device.
Congratulations, you just jailbroke iOS 5.0.1. For a more comprehensive RedSn0w guide, head over to our RedSn0w page.
Were you able to jailbreak successfully?