Problem adding a new Window from Library in Interface Builder

I am trying to add a UIWindow through interface builder. Whenever i drag a window from the library, its default size is 320x480 As I am designing an app for iPad, I want this to be 768x1024 The values are greyed out but changes when resizing with the help of mouse开发者_开发技巧. Any one had this Issue before? Any help is appreciated.

Thanks

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You should use UIViews instead of UIWindows.

Edit: Sorry, didn't read correctly. Here my answer after reading carefully: Is the device set to iPad in the target section? Did you try to delete the xib and add a new MainWindow.xib.