custom urlheader for blog in asp .net
===

net mvc 3 and trying to create a blog application. I want to have a url which contains a urlheader such as:

Blog/Details/Third-post

However, I am getting a url which is this:

Blog/Details/3?urlHeader=Third-post

what am I doing wrong?

My blog controller is as follows:

    public ViewResult Details(int id, string urlHeader)
    {
        var blogs = blogrepository.GetBlog(id);
        var recentblogs = blogrepository.FindRecentBlogs(5);
        var archivelist = blogrepository.ArchiveList();
        BlogDetailsViewModels viewModel = new BlogDetailsViewModels { Blog = blogs, RecentBlogs = recentblogs, ArchiveList = archivelist };
        return View(viewModel);
    }

and the route method is as follows:

   routes.MapRoute(
        "BlogDetail", // Route name
        "Blog/Details/{urlHeader}", // URL with parameters
        new { controller = "Blog", action = "Details" }, // Parameter defaults
        new { urlHeader = "" } // Parameter constraints
    );

and the link is as follows:

    @Html.ActionLink(Model.Title , "Details", "Blog", new { id = Model.BlogID, urlHeader = Model.UrlHeader }, null)

Thanks!