Hello guys or girls..!

I'm new in ASP.NET and I have a problem...

When I want to cache I View or an Action like this :

<%@ Page title="" language="C#" masterpagefile="~/Views/Shared/MemberHome.Master" inherits="System.Web.Mvc.ViewPage<IndexViewData>" %>
<%@ OutputCache duration="400" varybyparam="divId;regionId;page" %> 

I know that it cache all data in my page ... But in my page I have a condition like this :

 <% if(Request.IsAuthenticated) { %>
                <a href="/fr/Advertiser/Search"><img src="/content/images/v_2/bot.jpg" alt="Entreprises liées à vos passions" title="Entreprises liées à vos passions" /></a>
            <% } else { %>
                <a href="/fr/Advertiser/OpenSearch"><img src="/content/images/v_2/bot.jpg" alt="Entreprises liées à vos passions" title="Entreprises liées à vos passions" /></a>
            <% } %>    

I dont want to cache this variable : Request.IsAuthenticated ... because some result depend of this condition ... I try the donut caching by scottgu's but it return (I think) just some text not a bool ... http://weblogs.asp.net/scottgu/archive/2006/11/28/tip-trick-implement-donut-caching-with-the-asp-net-2-0-output-cache-substitution-feature.aspx

Now I'm tired to try anything that come to my mind .. can you help me pleaseee! :)

Julien.