"Session is Closed!" - NHibernate

This is in a web application environment:

An initial request is able to successfully complete, however any additional requests return a "Session is Closed" response from the NHibernate framework. I'm using a HttpModule approach with the following code:

public class MyHttpModule : IHttpModule{    public void Init(HttpApplication context)    {        context.EndRequest += ApplicationEndRequest;        context.BeginRequest += ApplicationBeginRequest;    }    public void ApplicationBeginRequest(object sender, EventArgs e)    {        CurrentSessionContext.Bind(SessionFactory.Instance.OpenSession());    }    public void ApplicationEndRequest(object sender, EventArgs e)    {        ISession currentSession = CurrentSessionContext.Unbind(            SessionFactory.Instance);        currentSession.Dispose();    }    public void Dispose() { }}

SessionFactory.Instance is my singleton implementation, using FluentNHibernate to return an ISessionFactory object.

In my repository class, I attempt to use the following syntax:

public class MyObjectRepository : IMyObjectRepository{    public MyObject GetByID(int id)    {        using (ISession session = SessionFactory.Instance.GetCurrentSession())            return session.Get<MyObject>(id);    }}

This allows code in the application to be called as such:

IMyObjectRepository repo = new MyObjectRepository();MyObject obj = repo.GetByID(1);

I have a suspicion my repository code is to blame, but I'm not 100% sure on the actual implementation I should be using.

I found a similar issue on SO here. I too am using WebSessionContext in my implementation, however, no solution was provided other than writing a custom SessionManager. For simple CRUD operations, is a custom session provider required apart from the built in tools(ie WebSessionContext)?