Windows Azure: Service Bus Relay

Service Host:

using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using System.Threading.Tasks;
using System.ServiceModel;

namespace Test.WCF.ServiceBus.Host.Service
{
    [ServiceContract(Namespace = "urn:ps")]
    interface IProblemSolver
    {
        [OperationContract]
        int AddNumbers(int a, int b);
    }

    interface IProblemSolverChannel : IProblemSolver, IClientChannel { }
}

IProblemSolver.cs