[civilsin]

I had this same problem. I thought at first it was a cell tower issue. I called US Cellular and asked. They said it was a known problem with this phone. They had me go into Settings-All Settings-Personal-Phone-CDMA services-Time Synchronization and click "get settings" Then uncheck the "Time Synchronize with mobile network automatically". Then I went and manually changed my time zone (on that same screen click "Clock&Alarm"). It stayed on that correct time zone.

BUT then I did some searching online and someone had said they manually updated "QuickGPS", then updated the weather tab and everything went back to normal. I noticed that I only had 4 hours left on QuickGPS. So I updated it and then updated my weather and everything went back to normal. I turned back on the network synchronization and everything still stayed in the correct time zone. So, maybe it's an issue with QuickGPS when it gets close to the end of it's time before it expires. Just a thought.