WCF service - is CallBackChannel alive

[Hanzaplast]

hi guys, this seems to be easy, but i just cant find right answer. i have WCF duplex service to host online poker game (silverlight on client). if one client plug of his cable or meteor strikes at his home i need to disconnect him. it is easy to implement method Disconnect, but i cant call it if user is unsuspectedly disconnected... my approach is: 1. enter - open page 2. connect - client calls method Connect wich is OperationContract on server; server have array field of all connected clients - CallbackContract 3. do something - send to server your move (irrelevant logic for this question) 4. check clients - this is what i dont have. i want to remove disconected users from my array field of all connected clients 5. recive info - server says what happend to all clients via CallbackContract OperationContext.Current.Channel.Closed and OperationContext.Current.Channel.Faulted sounds like what i need, but they act strange?

public class Poker : IPokerService
{
HttpContext appContext;

    HttpContext AppContext
    {
        get
        {
            if(appContext == null)
                appContext = HttpContext.Current;
            return appContext;
        }
    }
    Dictionary<string, IPokerClient> ClientList
    {
        get
        {
            object temp = AppContext.Application\["ClientList"\];
            if (temp == null)
            {
                temp = new Dictionary<string, IPokerClient>();
                AppContext.Application\["ClientList"\] = temp;
            }
            return (Dictionary<string, IPokerClient>)temp;
        }
    }
public void Connect(string id)
    {
        Dictionary<string, IPokerClient> clientList = ClientList;
        try
        {
            IPokerClient client = OperationContext.Current.GetCallbackChannel<IPokerClient>();
            if (!clientList.ContainsKey(id))
                clientList.Add(id, client);
            else
                clientList\[id\] = client;
            OperationContext.Current.Channel.Faulted += new EventHandler(Channel\_Faulted);
            OperationContext.Current.Channel.Closed += new EventHandler(Channel\_Closed);
        }
        catch
        {
            //later
        }
    }
void Channel\_Closed(object sender, EventArgs e)
    {
    }