title: __doPostBack on event works only once
body: <p>I have a hidden asp control that has a server event to it (valuechanged). I call the javascript __doPostBack method and as a parameter I send the id of the hidden control which makes it raise the valuechanged event after the Page_Load. It works fine for the first time, but the other times it posts back without raising the event.
  Is there anything I am missing here? Is it caching the postback?</p>
  
  <p>EDIT:</p>
  
  <p>The hidden field is in an updatepanel, so the __doPostBack doesn't refresh the whole page</p>