Log out using forms authentication in SP2010

Question

I have configured an intranet using Claims based authentication and an extended internet site using forms based authentication in SP 2010

All is set up and working except logging out...

I have a loginstatus control which I have placed a linkbutton inside the loggedin template. When I click the button to log out, I have used:

 Session.Abandon();
        Response.Cookies.Clear();
        FormsAuthentication.SignOut();

And a custom redirect. ~However when I get redirected back to my home page the system still says that Im logged in and I navigate around the site. How else do I force a logout?