Thanks for your guidance, cyanogen-man. After a phone reset didn't fix the problem, I took it to the Sprint store. They ordered me a new one using my insurance, to come in 2 or 3 days. In the meantime, my phone has resumed working. Now I am unsure what to do. If they are providing a new phone, I think I better take it. But if it's a refurb, I'm not sure I want to use my insurance on it. I once had more problems with a Treo refurb than with the phone I'd traded in!