Objective-C restart iphone or possibly another method?

I read that there was no method to restart the iPhone (at least that will go through the app store), so I am wondering if you have any other ideas. Basically, at my desk, I receive "No Service"... When I go out to my car (in a service area), I remain in No Service without being able to make a call until I restart my iPhone. I开发者_StackOverflow中文版've tried respringing winterboard, I've tried airplane mode on/off and that doesn't work either. The only way I've found is to restart the iPhone completely. Does anyone else have any ideas?

Thanks!

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Your explanation is right on the money. Nothing you can do about this particular problem outside of jailbreaking.