Blank "call received" screen appears seemingly at random
Apologies in advance if this has been posted before but a forum and Google search came up with nothing. It doesn't help that I wasn't sure what to call this issue!
I just unlocked an iPhone for a friend. The process was identical to my iPhone:
1.0.2 -> 1.1.1 and then unlocked via anySIM.
I used independence on Mac OS X to assist me with the brute work. I have also modified the AppSupport framework and UIPhoneFormat.plist to acclimatise the phone to Australia but otherwise the phone is unmodified.
Now here's the odd thing. Every so often, seemingly at random, a totally blank call received screen will appear with no name, number or image but it does have the "Cancel" and "Accept" buttons at the bottom. The iPhone also doesn't ring or vibrate. Pressing either button removes the screen and sends the phone back to the screen it was on.
However, the phone happily receives calls and displays them correctly.
Does anyone have any idea what is causing it? I'm hazarding a guess that the AppSupport framework is messing around but it's a copy of the framework on my iPhone which works perfectly.
Thanks in advance for any assistance you can give.