Sharepoint 2010 ClientContext with kerberos & a 401 unauthorised
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I can get a remote console app talking to a NTLM Sharepoint site with ClientContext and I can it talking to a remote Kerberos Sharepoint box with HttpWebRequest.GetResponse();

But I cannot get it talking to the Kerberos Sharepoint box with CientContext.  Any additional pointers would be gratefully recieved.  

             
    string siteURL = "http://my.remote.sharepoint";             
    ClientContext ctx = new ClientContext(siteURL);           
    CredentialCache cc = new CredentialCache();           
    cc.Add(new Uri(siteURL), "Kerberos", CredentialCache.DefaultNetworkCredentials);            
    ctx.AuthenticationMode = ClientAuthenticationMode.Default;         
    ctx.Credentials =cc;

    /////////////////////////////////////////////////////////////////////////////////
    // This code confirms that I can access "my.remote.sharepoint" with KRB
    //       HttpWebRequest myRequest = (HttpWebRequest)WebRequest.Create(siteURL);
    //       myHttpWebRequest.Credentials = cc;
    //       myHttpWebRequest.UseDefaultCredentials = true;              
    //       HttpWebResponse myResponse = (HttpWebResponse)myRequest.GetResponse();
    /////////////////////////////////////////////////////////////////////////////////
    Web remoteWeb = ctx.Web;
    ctx.Load(remoteWeb);
    ctx.ExecuteQuery();

    //401 unauthorised returned from here

Wireshark suggests that it returns the initial 401 & then gives up!  Any ideas