title: fileupload not working on window.showModalDialog
body: <p>I am looking to open a aspx page to act an an image uploader.. this is the code I use to open the page:</p>
  
  <pre><code>$("#btnUpload").on("click", function (s) {
      s.preventDefault();
      var id = $('#hdnId').val();
      var response = window.showModalDialog("/imageUpload.aspx/", id);
      alert(response);
  });
  </code></pre>
  
  <p>the page opens fine and looks like this:</p>
  
  <pre><code>&lt;head runat="server"&gt;
      &lt;title&gt;&lt;/title&gt;
  &lt;/head&gt;
  &lt;body&gt;
      &lt;form id="form1" runat="server"&gt;
          &lt;div&gt;
              &lt;label&gt;Choose New Image:&lt;/label&gt;
              &lt;br/&gt;
  
              &lt;asp:FileUpload ID="imageUploader" runat="server"&gt;&lt;/asp:FileUpload&gt;
  
              &lt;asp:Button id="UploadButton" OnClick="UploadButton_Click" Text="Upload file" runat="server"&gt;&lt;/asp:Button&gt;     
          &lt;/div&gt;
      &lt;/form&gt;
  &lt;/body&gt;
  &lt;/html&gt;
  </code></pre>
  
  <p>The fileupload renders ok on the page - but the choose file button doesn't work at all! ive watched in chrome &amp; there are no jquery errors on page load or on click of the choose file button. </p>
  
  <p>I've done a bit of googling and found that ajax and update panels are dodge with the fileuploader - But i'm not using either :-/</p>
  
  <p>anyone know whats occurring here?? many thanks</p>