I Activated and Jailbroke my UK Iphone and have been using an O2 simplicity sim in it for a few days.
Everything seemed fine at first but am now experiencing a problem with is becomming more frequent.
I can use the phone for a while by browsing the internet or using the Ipod to watch a video or play music but then when I come out of the application back to the Spingboard and try and use another application, that is when the problem occurs.
When I try and go into the next application it starts to load it but then boots me back to the Summerboard. I can then try and go into another application and it will do the same thing again. I try this three or four times and it will eventually shove me back to the unlock screen and then reboot.
After the reboot it will be fine.
Seems like something is wrong with the unlock/activate. I mainly used the following guide - http://www.hackint0sh.org/forum/showthread.php?t=15932.
Anyone got any ideas?