I would like to resize a window/image in a nib at load time.

Question

I have an iPhone app that I'm porting to the iPad. I store several of the ViewControllers in xib's that I would like to resize when they're loaded. For example my startup screen with options is a bitmap that can easily scale up (despite the mis-matched aspect ratio) and I'm trying to figure out where I have ability to resize the image/window during xib loading.