I'm on a different continent and using different carriers. I switched from AT&T (no 3G) to T-Mobile (3G) and never had the "no cellular" error with AT&T but already experienced it a couple times per day with T-Mobile. I just chalk it up to poor coverage (their maps show full coverage for the areas in which I live, work and travel... but...) I wonder if the phone is not able to gracefully handle these situations as well as other phones? It seems like once it loses the cellular signal, it has a hard time reconnecting to the network. I use the 3G/2G mode selection applet to "kick start" this process. Usually when it has no signal, if i change the mode it'll magically have 3 bars of signal or more...