AT&T Unlock iPhone 4 without a Sim Card installed question
I just put in my request to unlock my iPhone 4 from AT&T.
My contract has expired, and my old phone number is no longer active as of about 2 weeks ago, I also no longer live in the US (I've already travelled abroad), but they said that it would have no problem to unlock my iPhone as it's all done via iTunes.
I still have my old AT&T Sim card, but the number is not activate and like I said I'm in another country.
I have heard for the unlock process to be completed you need an activate sim card installed in the phone. Does it matter what carrier's sim I use (can I use a local one?) or does it absolutely have to be an AT&T sim?
I'm in Dubai now and have an active prepaid du sim card (they said it can easily be cut to micro-sim).
Contacing AT&T from here is a nightmare (the "international" number they gave me won't dial out and the website won't let me access my old account info since it's closed now and thus can't access their web chat either).
iPhone 4, iOS 5.0.1