Upgraded my iPhone 4 to 5.0.1 a week or two ago. I only showed 1 signal and the version of ultrasn0w available at the time 1.2.4 didn't support 5.0.1. No worries I waited. Now ultrasn0w is at 1.2.5 and supports 5.0.1. I installed it and it fixed the signal problem. Cool right? Well later that night I pick up my phone and it shows no service. A respring didn't fix. And only after 2 reboots did it show signal again. It happened again like 10 min ago and I couldn't fix the problem. So as it stands now I have uninstalled ultrasn0w 1.2.5 and seeing if anyone else has this problem.