Using ASP .NET Ajax UpdateProgress Control

Source Code:
<%@ Page Language="VB" AutoEventWireup="false" CodeFile="mPbar.aspx.vb" Inherits="mPbar" %>
<%@ Register Assembly="AjaxControlToolkit" Namespace="AjaxControlToolkit" TagPrefix="ajax" %>

<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd">

<html xmlns="http://www.w3.org/1999/xhtml">
<head runat="server">
    <title>Untitled Page</title>
</head>
<body>
    <form id="form1" runat="server">
      <ajax:ToolkitScriptManager ID="tl" runat="server"></ajax:ToolkitScriptManager>
<table class="style1">
   <tr>
      <td>
         <asp:UpdatePanel ID="UpdatePanel1" runat="server">
            <ContentTemplate>
               <asp:Button ID="Button1" runat="server" Text="Show Server Time"
                  OnClick="Button1_Click" />
               <asp:Label ID="Label1" runat="server"></asp:Label>
            </ContentTemplate>
         </asp:UpdatePanel>
      </td>
      <td>
         <asp:UpdatePanel ID="UpdatePanel2" runat="server">
            <ContentTemplate>
               <asp:Button ID="Button2" runat="server" Text="Show Server Time"
                  OnClick="Button2_Click" />             
               <asp:Label ID="Label2" runat="server"></asp:Label>
            </ContentTemplate>
         </asp:UpdatePanel>
      </td>
   </tr>
   <tr>
      <td>
         <asp:UpdateProgress ID="UpdateProgress1" runat="server"
            AssociatedUpdatePanelID="UpdatePanel1">
            <ProgressTemplate>
               <img alt="" src="p.gif" /> Updating ...
            </ProgressTemplate>
         </asp:UpdateProgress>
      </td>
      <td>
         <asp:UpdateProgress ID="UpdateProgress2" runat="server"
            AssociatedUpdatePanelID="UpdatePanel2">
            <ProgressTemplate>
               <img alt="" src="p.gif" /> Updating ...
            </ProgressTemplate>
         </asp:UpdateProgress>
      </td>
   </tr>
</table>
    </form>
</body>
</html>


VB Code:


Partial Class mPbar
    Inherits System.Web.UI.Page

    Protected Sub Button1_Click(ByVal sender As Object, ByVal e As System.EventArgs) Handles Button1.Click
        System.Threading.Thread.Sleep(2000)
        Label1.Text = DateTime.Now.ToString("hh:mm:ss tt")

    End Sub

    Protected Sub Button2_Click(ByVal sender As Object, ByVal e As System.EventArgs) Handles Button2.Click
        System.Threading.Thread.Sleep(2000)
        Label2.Text = DateTime.Now.ToString("hh:mm:ss tt")
    End Sub
End Class


Thanks