UITabBarController now kills inflight UIKit animations when switches between tabs?

I have an app that has UITabBarController with two UIViewControllers as its tabs. In the first UIViewController.view I have a continuous animation with repeat count set to INT_MAX. It worked fine until 3.2 and 4.0. On 3.2 or newer, when I switch to a different tab, OS skips to the end of my animations and invokes -animationDidStop:finished:context: on its animation del开发者_运维技巧egate. Any ideas how to make sure that animations will not be destroyed when tabs are switched?