But why not take it a step further and present the standard KB? That would be a slight inconvenience, with a massive gain in confusion for anyone trying to guess their way in.
I had a bug recently on my Windows Phone after adding my corporate email account to Outlook. I assume it was some sort of group policy being erroneously applied, but it turned out to be a massive inconvenience.
Mostly because trying to unlock it displayed the standard keyboard[1], but simply wouldn't allow me to create a PIN with anything other than numeric characters[2], so every time I needed to unlock my phone I had to swipe the screen up, then change the keyboard over to the number/symbol mode, and enter my PIN using the small row of numbers there.
In the end, all I had to do was change my pin, and from that moment on, it only ever displayed the standard number pad for unlocking.
