Flip UIView pre-iOS 4 from left to right

I know there's a simple UIViewAnimationOptionTransitionFlipFromLeft and way to implement that, but how do you do something similar (i.e. 开发者_如何学Goflip a UIView over) pre-iOS 4, like on the iPad, for example.

[UIView beginAnimations: @"flipOverCard1" context: nil];
[UIView setAnimationDuration: 0.5f];
[UIView setAnimationTransition: UIViewAnimationTransitionFlipFromLeft forView: card1 cache: YES];

// Stuff to do while transitioning

[UIView commitAnimations];