ok so im on version 4.0.1 iphone 4, i have never upfated since i got the phone to keep the jailbrake but im having problems now with cydia and some apps require higher FW is there any way i can upgrade w/o lossing my jailbrake or what would b the best way to do it i know 4.3.1 is out and i belive there is a jailbrake for it but is that the best thing to do?