How can I change my map route so I can have another dir, and not just the controllers and actions.

What I want is to have another directory before the controller so that way I can separate controller per "module"

        routes.MapRoute(
            "Default",                                       // Route name
            "{module}/{controller}/{action}/{id}",           // URL with params
            new { module = "module", controller = "controller", action = "Index", id = ""}

This is what I want, but the code doesn't work. What more do I need to change to change the MapRoute?