OK, this is driving me crazy. I live in China. I have three iPhone 4 phones that I bought last year directly from Apple at full retail, factory unlocked. I updated all of them to iOS5 on basically the first day the software was released (last week). Got everything set up and going, and for the first full day I was able to send / receive iMessage with my wife no problems whatsoever. Then, suddenly I noted that iMessages weren't sending (tried to send an MMS, and it said delivery failed). Checked settings and found that iMessage said "waiting for activation". I have tried turning off/on iMessage a billion times. Each time, it activates my email address for iMessage, but not my phone number. Usually each time I turn on iMessage, I get a weird text message that looks like some kind of silent SMS command coming from a UK number (+0044xxxxx, REG-RESP blah blah blah). After a while it says "activation failed" or something like that. I made the mistake of turning iMessage off on my other phones, and when trying to turn it back on it does the same thing now. On twitter it looks like there are quite some people who also have this problem, though not really a flood. WTF. I just flew to Eurpoe (Norway), and it's doing the same thing from here. I have no idea if this is a phone problem, a bug, a carrier problem, Apple's servers being overloaded, what what what. It's been two days now. Any ideas?