Updating multiple records at once with update action

I have a model called Setting, and I want to be able to edit and update
multiple settings at once. Therefore I added this resource to routes.rb:

map.resources :settings, :collection => {:edit => :get, :update => :put}

As you can see I want to edit and update _collections_ of settings, not
just a single Setting at a time.

When I run "rake routes" I get the following routes as expected:

update_settings PUT /settings/update {:controller=>"settings",
te", :id=>/[^\/.?]+/}
edit_settings GET /settings/edit {:controller=>"settings",
:action=>"edit", :id=>/[^\/.?]+/}

But as you can see, both the edit and update actions still require me to
set an id! But since I'm updating multiple settings, that's not

This (I'm using HAML):

- form_tag update_settings_path, :method => "put" do

generates this error:

update_settings_url failed to generate from {:action=>"update",
:controller=>"settings"}, expected: {:id=>/[^\/.?]+/, :action=>"update",
:controller=>"settings"}, diff: {:id=>/[^\/.?]+/}

How can I solve this? I am not so much into regular expressions, but
it's just requiring a number, right?

If none of you have a suggestion, I'll post a ticket to Rails'