title: upgrade to universal app - size of mainWindow-iPad is 320x480
body: <p>I have the following problem.
  I have an iPhone app and want to upgrade to universal
  When I do this, I get the expected MainWindow-iPad.xib.
  But the size of the window is hardcoded to 320x480.
  Also, there is no view in the window.
  I red, this should be automatically iPad-sized, so I am assuming I am doing something wrong.
  What exactly am I missing ?
  thanks in advance</p>