Ive been converted!!!

Im using this to create .aspx page.

<?xml version="1.0" encoding="utf-8"?>
<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd">
<%@ Page Language="C#" ContentType="text/html" ResponseEncoding="utf-8" %>
<html xmlns="http://www.w3.org/1999/xhtml">

But want to use mobilecontrols to detect useragent and send approiate content, using the Nmbs 4. all this code appears with the content. Whats wrong! this cant be right. Help!!

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