title: How to get an error description when playback fails on MPMoviePlayerController
body: <p>I want to show an <code>UIAlert</code> if the Video-Play fails. So i registered the <code>MPMoviePlayerPlaybackDidFinishNotification</code> for my Movie Player:</p>
  
  <blockquote>
    <p>[[NSNotificationCenter defaultCenter] addObserver:self selector:@selector(myMovieFinishedCallback:) name:MPMoviePlayerPlaybackDidFinishNotification object:self.moviePlayer];</p>
  </blockquote>
  
  <p>In my myMovieFinishedCallback: I check if in the User Info Dictionary is a Object named  <code>error</code>. On my real device I don't get this error (on no network error, 404 error for file). On the iPhone Simulator I receive the error.</p>
  
  <p>How can I properly check the reasoning when I receive the <code>MPMoviePlayerPlaybackDidFinishNotification</code>?</p>