I have a few UITextViews in my App. Since I have started building from XCode 4.5 the UITextView is sort of not editable in iOS6 but built on an iOS5 device they are fully ed
In my case this happened because the UIAltertView was called twice.
UIAltertView
You might not think you never typed any keys, but the BackSpace key does qualify.
Then I removed the second UIAlertView and the TextField worked.
UIAlertView
TextField
I think you need to check the UIAlertView code.