My gps stopped working about a week ago. It doesn't track my movements and consistantly about 1/4 mile off. I thought it was the nike+ gps app I installed so I got rid of that but it still doesn't work. So yesterday I updated my firware to 4.2.1 but I still have the issue. I'm on a jailbroken 3gs firmware 05.15.04 I've try turning the 3g off and on, deleting the cache.plist file in var/root/library/caches/locationd. Nothing has worked so far, so if any one has any ideas or solution that would be great.