The MessageForwardingModule may be found in the Shuttle.Esb.Modules assembly. The module will attach the MessageForwardingObserver to the OnAfterHandleMessage and then send the handled message on to any defined endpoints.
<messageForwarding>
<forwardingRoutes>
<messageRoute uri="msmq://./inbox">
<add specification="StartsWith" value="Shuttle.Messages1" />
<add specification="StartsWith" value="Shuttle.Messages2" />
</messageRoute>
<messageRoute uri="sql://./inbox">
<add specification="TypeList" value="DoSomethingCommand" />
</messageRoute>
</forwardingRoutes>
</messageForwarding>
var bus = ServiceBus
.Create(c => c.AddModule(new MessageForwardingModule()))
.Start();
The specifications are the same specifications used by the DefaultMessageRouteProvider implementation.