title: update panle not working correctly
body: <p>In my website i used update panel in modal popup to avoid post back. All are working well except one. In this i've three dropdownlists and they are populating in a sequence i.e First one is populated on Page Load, second on the index changed event of first list and third list is populated upon the index changed in second list.
  On changing the index in first list second get changed but the problem is on index changed in second list nothing happened!
  Third list is not populating on Index Changed</p>
  
  <p>I'm populating lists from database via page methods.</p>
  
  <p>Any help would be great!</p>