Use VS2005, VB.NET code behind,

I've got a page with the following code snippet on it:

    <p>
        <asp:Button ID="btnHelp" runat="server" Text="Help" />
    </p>
    <asp:Panel ID="Panel1" SkinID="PopUpSkin" runat="server">
        <h3>Help - Under Construction</h3>
        <p>
             <asp:Label ID="Label1" runat="server" Text="a bunch of 
                sample text here... a bunch of sample text here...
                a bunch of sample text here... a bunch of sample text
                here... "></asp:Label><br />
        </p>
        <p style="text-align: center;">
            <asp:Button ID="btnClose" runat="server" Text="Close" />
        </p>
    </asp:Panel>
    <ajaxToolkit:ModalPopupExtender ID="ModalPopupExtender1" runat="server" TargetControlID="btnHelp"
        PopupControlID="Panel1" BackgroundCssClass="modalBackground" OkControlID="btnClose">
    </ajaxToolkit:ModalPopupExtender>

Thanks