Mobile Control ASP.Net

<%@ Page 
    Inherits="System.Web.UI.MobileControls.MobilePage" 
    Language="VB" 
%>
<%@ Register 
    TagPrefix="mobile" 
    Namespace="System.Web.UI.MobileControls" 
    Assembly="System.Web.Mobile" 
%>


    id="FirstPage" 
    runat="server">
            advertisementfile="AdRotatorBasic.xml" 
        runat="server"
    />