An apartment I lived in had a similar system. I noticed that the caller ID showed what appeared to be a valid number. So one day I tried calling it while at the door... when it started ringing, I started hitting buttons on the keypad (on the door) and when I hit the # key (or maybe it was *), it picked up. I was then able to dial 9 from my phone, and it let me in.
I no longer live there, and don't have access to an apartment that has one. I'd be interested to see if that works on other systems. If anyone wants to try, let me know if it does.
This is something that Apple could totally provide at a global level. Subclasses of the UIViewController can override the willRotateToInterfaceOrientation:duration: method to define how they want to handle rotation events. Apple could modify the UIViewController's default behavior to not send rotation messages if a global "don't rotate" setting is set to true.
I no longer live there, and don't have access to an apartment that has one. I'd be interested to see if that works on other systems. If anyone wants to try, let me know if it does.