Eric_G1,
Thanks for the prompt reply.
I've actually tried all the suggestions you offered, with no change in the behavior of the phone. However, I think I now know what is causing the problem.
The phone was hand-carried from the US to me at my home in Kenya. It seems that the Security Services feature is available there, but not here. I believe the iPhone tries incessantly to find the service, racking up cellular data charges at an unbelievable pace. More importantly, I've discovered that there is a work-around: keep cellular service off at all times.
At home, my iPhone operates on a modem, so cellular access is unnecessary. When out and about, I can use local business wi-fi's to handle any work I want to accomplish on the iPhone. While driving, we mustn't be using phones anyway, but in case of a breakdown or accident, the phone operates with or without cellular if airtime is topped up.
In short, then, I can live with the situation. What I would recommend is that Apple put a switch on the Security Services feature so that anyone bothered by the excessive data consumption can actually turn it off. Let's pray that something of that nature appears in the next iOS update!
Cheers, and thanks again!
Dena