title: Flex: indeterminate ProgressBar in modal pop up?
body: <p>Whenever I set a indeterminate progress bar in a modal pop-up via PopUpManager, there is no progress displayed. If I add the same ProgressBar to the parent regularly or make the pop-up non-modal it works. Is there a reason why it doesn't work in modal pop-ups? and a way to make it work?</p>
  
  <p>Thanks.</p>