Spent a couple of hours today trying to jailbreak my iPod. After numerous attempts, I was on the point of giving up when I found this forum post with a solution: Run greenpois0n from the command line, rather than from the GUI.

While the forum post refers to RC5_2, I can confirm that it works with RC6 also. Here’s my method.

1. Make sure that your iPod is connected to your computer.
2. Shut down iTunes if it’s open.
3. Turn off your iPod.
4. Hold the power button and home button for 10 seconds.
5. Release the power button, keep holding the home button for a further 10 seconds.
6. Open Terminal.
7. Change directory to the location of the greenpois0n app.
8. Type open ./greenpois0n.app/Contents/MacOS/greenpois0n
9. A new Terminal window will open and greenpois0n should now be able to jailbreak your iPod.
10. Wait for your iPod to restart.
11. Find the green Loader icon on your iPod and use it to install Cydia.

And that’s it – you’re good to go!