Hi Sony - Have you specified the route in your routes.rb file?
Try adding
map.resources :items, :member => {:list => :get}
or
map.resources :items, :collection => {:list => :get} if this action is not for one specific object at a time.
this will give you list_item_path(@item) or list_items_path
That might help with the routing issue.
Here's a great tutorial on routes: http://guides.rubyonrails.org/routing_outside_in.html