title: Missing Frameworks iOS 4.0
body: <p>I've just updated xcode to release 4.0. A lot of the frameworks in my App are now highlighted in red, they appear to be missing. i.e. MapKit.framework</p>
  
  <p>Is 4.0 not backward compatible with 3.1.3 ?</p>
  
  <p>Regards,
  Stephen</p>