title: TextChanged event not being triggered with UpdatePanel
body: <p>I have 2 textboxes: txtSKU1 and txtDescription1. I want the user put text into txtSKU1, then hit tab and have the txtSKU1_TextChanged event fire, which will auto populate txtDescription1. I'm trying to avoid using a postback. From my understanding, the TextChanged event fires after it loses focus, so I assumed the UpdatePanel I used below would work but nothing happens until I do a trigger a postback. Any ideas?</p>
  
  <pre><code>&lt;td&gt;&lt;asp:TextBox ID="txtSKU1" runat="server" width="100%" BorderColor="#dddddd" OnTextChanged="txtSKU1_TextChanged"&gt;&lt;/asp:TextBox&gt;&lt;/td&gt;
      &lt;td&gt;
              &lt;asp:UpdatePanel ID="UpdatePanel1" runat="server" UpdateMode="Conditional"&gt;
                  &lt;ContentTemplate&gt;
                      &lt;asp:TextBox ID="txtDescription1" runat="server" width="100%" BorderColor="#dddddd"&gt;&lt;/asp:TextBox&gt;
                  &lt;/ContentTemplate&gt;
                  &lt;Triggers&gt;
                      &lt;asp:AsyncPostBackTrigger ControlID="txtSKU1" EventName="TextChanged" /&gt;
                  &lt;/Triggers&gt;
              &lt;/asp:UpdatePanel&gt;
      &lt;/td&gt;
  </code></pre>