WCF: CallbackChannel error

Question

Hi there,

I have some C# code, the server app, that access a WCF service, thE client app, using a WCF service hosted in the client app

WheN the server connects to the client it uses a DuplexChannelFactory and passed in an instance of a class to be used for the client to talk back to the server

The client is a singleton i.e.

[ServiceBehavior(InstanceContextMode = InstanceContextMode.Single)]

the client talks back the server using

mCallBackChannel = OperationContext.Current.GetCallbackChannel<IClientCallBack>();
mCallBackChannel.MethodOnServer();

It all works fine until the server dies. When this happens OperationContext.Current is always null even when the server create a connection to the host again, so the client cannot call back the server.

What are my options here?

Note that it needs to stay a singleton and I need to connunicate back using the call back channel i.e. not a WCF server hosted in the server app for example