Nested REST routes not working

I started using REST in EdgeRails and it started out going alright.
But, when I nest routes and try to do the handy-dandy named routes I
get an error.

Here are my routes:

  map.resources :product_stockeds do |product_stocked|
    product_stocked.resources :product_inventory_items

Then from http://localhost:3000/product_stockeds/1, I try to call:

<%= link_to 'Inventory Items', product_inventory_items_url %>

But I get the error:

product_inventory_items_url failed to generate from {:action=>"index",
:controller=>"product_inventory_items"}, expected: {:action=>"index",
:controller=>"product_inventory_items"}, diff: {}

Any help on this would be greatly appreciated. I am completely lost.