Samsung Vibrant :: Losing Data Connection Permanently After Being In No-service Zone.

Most of the time the data connection works fine. But if I go into an area with no cell phone reception for a little while, once I come out into a full-bars area where data normally works, my data connection never resumes. Once that happens, I can make calls just fine, but can't use the internet/market/etc. The only thing that solves this problem is to go to network settings, enable 2G networks only, then turn that setting off. That is a huge pain, obviously. Has anyone else had this problem? This was happening with my old SIM, so I had T-mobile give me a brand new one, but it is still happening.