uinavigationcontroller - Upside down on iPhone iOS 6?

Question

Possible Duplicate:
Rotation behaving differently on iOS6

I want my app to support the upside down orientation on the iPhone. This works in iOS 5, but I'm having difficulty making it work on iOS 6.

Apple's documentation mentions that the default supported orientations are everything on iPad, and everything except upside down on iPhone. I want to support everything on both; I have personally run into situations where wires are in the way in standard portrait mode, and don't want to arbitrarily decide for my users that they can't use the app upside down if they have a similar problem.

Here's what I've done so far:

1. My view controller's shouldAutorotateToInterfaceOrientation; return YES for all orientations, as required for iOS 5. (I have also tried commenting out this view controller's shouldAutorotateToInterfaceOrientation:, on the off chance that iOS 6 made decisions based on its presence. It did not help.)
2. My view controller's supportedInterfaceOrientations returns UIInterfaceOrientationMaskAll.
3. My application delegate's application:supportedInterfaceOrientationsForWindow: returns UIInterfaceOrientationMaskAll.
4. All orientation modes are selected in the target's summary page.

What am I missing?