Just thought I'd post with my info. I played the free version on my Iphone 3G for several days without problems before moving up to the paid version recently. Since then I've had random resets upon re-entering the game (about once per day). I haven't messed with the phone's clock. I simply exited as I normally would and found the game had reset the next time I logged on. Just for reference, I didn't even use the phone between logging off and logging back on the last time. Also, I updated the game to 1.0.2 already so I know it's with the new update.
Hope you guys can resolve this. It's a great game otherwise!