UIScrollView not working

I have a UIScrollView with a View inside of it. Inside of that view is a bunch of buttons, labels, etc that fit in the View when in Portrait mode...When the iPad is rotated, I want the scrollView to kick in so the user can scroll to the bottom of the view. The app runs, but when I rotate it, the scroller never works...I believe I've wired everything up correctly and I have this code in the viewDidLoad event:

[scrollview addSubview: masterView];
scrollView.contentSize = [masterView sizeThatFits:CGSizeZero];

Is there something else I am missing? Do I need to modify the size when the iPad rotates?

thanks

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