Why are my popovers not auto-rotating when I rotate my device?

In my current app, when I rotate my iPad with popovers containing an ImagePicker or a PickerView currently displayed on the screen, they don't rotate correctly and appear on their sides instead of rotating.

Anyone know why?

A further puzzle is that it works fine on the 4.3 simulator, but not on my 5.0 beta 4 iPad. Unfortunately I don开发者_开发百科't have a 4.3 iPad to try it on.