title: visibility issues with IE9 using jquery to add item to listbox
body: <p>I am adding an item to a listbox from an input textbox.  Things work fine in chrome and firefox, however when I click the button to add the text to the listbox in IE9 the item gets added but it is not visible.  WHen I click my save button the item i added shows up in the collection, it just doesnt view in the listbox.</p>
  
  <p>below is my jquery:</p>
  
  <pre><code>$('#addToListBox1').click(function () {
  var textValue = $('input[name=classIdInput]').val();
  
  $('#listbox1').append(
      new Option( 
          textValue,
          textValue
      ));
  });
  </code></pre>
  
  <p>wierd behavior for IE9... any ideas why the added text to the listbox has a position though you cant see it?
  thx</p>