How to log the raw xml messages in WCF

WcfMessageLogger.cs

using System;
using System.Collections.Generic;
using System.Diagnostics;
using System.Linq;
using System.ServiceModel.Configuration;
using System.ServiceModel.Description;
using System.ServiceModel.Dispatcher;
using System.Text;
using log4net;

namespace TechProtect.Backbone.Service
{
    public class WcfMessageLogger: IDispatchMessageInspector, IServiceBehavior
    {
        ILog log;

        public WcfMessageLogger(ILog log) 
        {
            this.log = log;
        }

        public object AfterReceiveRequest(ref System.ServiceModel.Channels.Message request, System.ServiceModel.IClientChannel channel, System.ServiceModel.InstanceContext instanceContext)
        {
            log.Debug(request.ToString());
            return null;
        }

        public void BeforeSendReply(ref System.ServiceModel.Channels.Message reply, object correlationState)
        {
            log.Debug(reply.ToString());           
        }

        public void AddBindingParameters(ServiceDescription serviceDescription, System.ServiceModel.ServiceHostBase serviceHostBase, System.Collections.ObjectModel.Collection<ServiceEndpoint> endpoints, System.ServiceModel.Channels.BindingParameterCollection bindingParameters)
        {            
        }

        public void ApplyDispatchBehavior(ServiceDescription serviceDescription, System.ServiceModel.ServiceHostBase serviceHostBase)
        {
            log4net.Config.XmlConfigurator.Configure();
            ILog log = LogManager.GetLogger(typeof(IMainService));

            foreach (ChannelDispatcher dispatcher in serviceHostBase.ChannelDispatchers)
            {
                foreach (var endpoint in dispatcher.Endpoints)
                {
                    endpoint.DispatchRuntime.MessageInspectors.Add(new WcfMessageLogger(log));
                }
            }
        }

        public void Validate(ServiceDescription serviceDescription, System.ServiceModel.ServiceHostBase serviceHostBase)
        {            
        }
    }

    public class WcfMessageLoggerExtension : BehaviorExtensionElement
    {
        protected override object CreateBehavior()
        {
            log4net.Config.XmlConfigurator.Configure(); 
            ILog log = LogManager.GetLogger(typeof(IMainService));

            return new WcfMessageLogger(log);
        }

        public override Type BehaviorType
        {
            get { return typeof(WcfMessageLogger); }
        }
    }
}