http://www.modmyifone.com/forums/showthread.php?t=25695&highlight=1.1.3+downgrade I have confirmed that this works. I went from 1.1.3 to 1.1.1 (didnt want to go back to 1.1.2). You need to have an older iphone that did not come pre-installed with 1.1.2 on it. I also confirmed that you can do this via Parallels, and dont need to boot a windows box. Make sure not to skip any steps!