iOS: Navigation Controller title bar shrinks in landscape mode when compiled, but not in Interface Builder

I'm trying to make an iPhone SDK 4.1 app, and I'm having some trouble with my Navigation Controller. When I set my app to portrait mode, everything looks like it should. However, when I set the initial orientation to landscape in my plist file and add the shouldAutorotateToInterfaceOrientation fun开发者_开发百科ction to my primary view controller, the Navigation Controller's title bar shrinks when compiled! For some reason, this change isn't reflected in Interface Builder, making it difficult to design my layout. Surely there's something I'm missing?

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