Ruby on Rails: remote_form_for to a different controller?

Question

How do I edit a Media but in an Attachment controller?

<% remote_form_for(@media, :controller => :attachments,
                :action => :add_from_disk, :proposal_id => @proposal,
                :html => { :multipart => true, :id => 'new_media', :onsubmit=>'unsaved_changes = false' } )  do |f| %>

currently, its still going to the media controller's create action. I don't want that.

Answer 1

<% remote_form_for(@media, :url => url_for(:controller => :attachments, :action => :add_from_disk, :proposal_id => @proposal),
                        :html => { :multipart => true, :id => 'new_media', :onsubmit=>'unsaved_changes = false' } )  do |f| %>

From: http://api.rubyonrails.org/classes/ActionView/Helpers/PrototypeHelper.html#M002178