title: UIActivityViewController - can't understand this memory leak
body: <p>Can someone please tell me why the following code is leaking in Instruments?  </p>
  
  <pre><code>UIActivityViewController *activityController = [[UIActivityViewController alloc] initWithActivityItems:activityItems applicationActivities:nil];
  activityController.excludedActivityTypes = [NSArray arrayWithObjects:@"a",@"b", nil];
  
  
  [self presentViewController:activityController animated:YES completion:nil];
  [activityController release];    
  </code></pre>
  
  <p>Instruments show the leak on row:  </p>
  
  <pre><code>activityController.excludedActivityTypes = [NSArray arrayWithObjects:@"a",@"b", nil];
  </code></pre>