title: Flex: Resetting prompt of a comboBox
body: <p>There is a <code>&lt;mx:ComboBox&gt;</code> component with <code>prompt = 'Please Select'</code>. User selects an option, save it, comes back tomorrow and want to undo it. How would he do that? Because prompt option is gone now.
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  Just to mention </p>
  
  <blockquote>
    <p>I am populating ComboBox values from database and there are thousands
    of comboBoxes in my application.</p>
  </blockquote>