title: AjaxControlToolkit combine scripts Sys.Extended.UI undefined
body: <p>I'm using the out-the-box script combining feature of the ajaxToolkit <code>ToolkitScriptManager</code> e.g:</p>
  
  <pre><code>&lt;ajaxToolkit:ToolkitScriptManager ID="manScript" runat="server" CombineScripts="true"&gt;&lt;/ajaxToolkit:ToolkitScriptManager&gt;
  </code></pre>
  
  <p>This works fine, the script resource files are combined which is the desired result however on certain pages, those which make use of the <a href="http://www.ajaxcontroltoolkit.net/ValidatorCallout/ValidatorCallout.aspx" rel="nofollow noreferrer">ValidatorCallout</a>, are breaking due to a script reference not being found:</p>
  
  <blockquote>
    <p>Uncaught TypeError: Cannot read property 'UI' of undefined</p>
  </blockquote>
  
  <p>Example:</p>
  
  <pre><code>Sys.Application.add_init(function() {
      $create(Sys.Extended.UI.ValidatorCalloutBehavior, {"ClientStateFieldID":"ctl00_ucBookingOverlayForm_vceEmailRfv_ClientState","closeImageUrl":"/WebResource.axd?d=f1QpGIE3tIwIlwHDSgFaMKzu_EDD74IJxTW0wu5XFBsijDtCLxDaIo2PLWkvmpuVhGM3qlhvBO657x4jHl-GgLAybfgjNbFabkTpkICSknrDRSEDk5EuUA23IYRXprVpF1a4fg2\u0026t=636155032911179735","highlightCssClass":"error","id":"ctl00_ucBookingOverlayForm_vceEmailRfv","warningIconImageUrl":"/WebResource.axd?d=J2f54MGVNKrbG7KUyE1UxWfAcESo9_Mj-3_tX4cOIGXtDsrNI96CS2rrIj0oLhO9ioIMaeIGa4hw-cuLd_AbF7V_P4hYubyJCjWCGBeOh8DYw-SCx23Kl5noFRHYQAgpnIVCKOe3QyH3vNqc8QhIYA93_YU1\u0026t=636155032911179735"}, null, null, $get("ctl00_ucBookingOverlayForm_reqLocation"));
  });
  </code></pre>
  
  <p>It's not finding <code>Sys.Extended.UI.ValidatorCalloutBehavior</code> for some reason. I'm guessing the script combining feature doesn't include this script? Because the error is resolved by setting <code>CombineScripts="false"</code>, this is no solution though as I need the script combining feature.</p>
  
  <p>I cannot upgrade to a new version of AjaxControlToolkit as the CMS I'm using has a dependency on this specific version (4.1.60919.0).</p>