UINavigationController back on landscape mode

[Amadeus]

i have 2 views in my application; view X and view Y
each view of them has 2 modes of portrait and landscape

when i'm on mode of portrait and go from view X to view Y
then i rotate to landscape; when i go back using this "[self.navigationController popViewControllerAnimated:YES];" the dimensions of all items are wrong, or else they are on the same positions of portrait mode.

how do i solve this
how can i check before going back from Y to X which mode i am on now.

or can i go back in "willAnimateRotationToInterfaceOrientation" function and it will handle the dimensions.

thanks