title: UIDocumentInteractionController or QLPreviewController can't zoom PDF on iOS5?
body: <p>I use QLPreviewController to view PDF files in one of my apps. However, ever since iOS5, users can no longer pinch to zoom in/out of the PDF. This is terrible for iPhone users, as they can't read anything.</p>
  
  <p>I have also tried using UIDocumentInteractionController but have had the same problem.</p>
  
  <p>Anyone know what's going on with this?</p>