I just upgraded from a jailbroken 1.1.1 to a jailbroken 1.1.3. Once I realized that my installer stopped working after a while, I just restored back to 1.1.1 and tried again. It works fine for a couple of hours, but a warning to those of you who want to try out 1.1.3 without losing all of your cool third party apps: don't sync on version 1.1.3. If you do, you can't restore back to 1.1.1. But, if you don't sync while with 1.1.3, you can just restore back to 1.1.1 whenever you want.