MVC :: Webforms Route / Implementing Route In Global.asax

I tried to mix asp.net 4 webfrom and ASp.Net MVC 3. I add required lines in webconfig, but I've issues implementing route in global.asax

Currently I use several routes for webfroms. routs template are like below

routes.MapPageRoute("Node", _
"article/sport/{nID}/", _
"~/article/articleview.aspx")

I encounter error, when I add below lines to global.asax

routes.MapRoute( _
"Defaultss", _
"{controller}/{action}/{id}", _
New With {.controller = "Home", .action = "Index", .id = UrlParameter.Optional} _
)

I want to know how could I mix ASp.Net MVC routes with webforms routes.