System.StackOverflow.Exception

Hi

this code gives System.StackOverflow.Exception at the bold line. Can anyone explain me how come?

Thanks

V

using System;
namespace test
{
    public partial class WebForm1 : System.Web.UI.Page
    {
        public Test ts = new Test();

        protected void Page_Load(object sender, EventArgs e)
        {
            Label1.Text = "ok";
        }
    }

    public class Test : WebForm1
    {
        string x;
    }
}

aspx file:

<%@ Page Language="C#" AutoEventWireup="true" CodeBehind="WebForm1.aspx.cs" Inherits="test.WebForm1" %>
....