yazzgoth.org

So you have upgraded your iPod to 1.1.2 by accident (or am I only one that stupid:P) and you’d like to downgrade back to 1.1.1 so you can jailbreak it?
Nothing easier done…
Download the 1.1.1 firmware
Start iTunes and click on the iPod on the left menu.
Hold down ALT and click on Update button. This will open a file selection menu, choose the firmware file you’ve downloaded.
After 1~2min you should be happy 1.1.1 iPod user now only a quick visit on jailbreakme.com and you’re done.