Coverage-switching zone. I've got these notifications before, and can replicate them fairly often. I travel into and out of KL by the RapidKL bus, so the route is already firmly set. I also travel up to work to KLIA using the ERL service from KL Sentral. Using these two predetermined routes(RapidKL bus route and ERL train route), there are several coverage-switching zones, that if I try and either send an SMS, make a call, or surf using 3G service, that the line will disconnect, and the message "Searching" will come out at the carrier designator area on top left. This means that the iPhone is switching between 3G coverage network to normal GSM or EDGE-enhanced GSM coverage network, and while this switching is going on, whatever network-related activities you are doing at that time, will be stalled until the iPhone latches on to a firm signal, and be able to carry out those specific tasks(send SMS, call, etc).

Nothing to worry about, just need to move back into coverage area, and you can resend that SMS back again. In fact, your SMS will remain typed on the text window until you tap the "Send" button again.

The whole fear of an iPhone not performing properly is fed by the previous act of jailbreaking/unlocking which the crowd may have induced notion that it messes with the telephony operation of the iPhone. The same fear has carried over, even to the days of official unlocks like today.

You only fear what you dont know.

Or maybe the high level of expectation of these new owners of the Jesusphone to work God-like miracles doing impossible things, even when it is clearly not the fault of the phone itself.

Let there be light!......I mean, line! *poof*