Monkey-patch that fixes Rails 2.3's `link_to` helper with method "delete" and fragment caching (just put the file in `config/initializers`)

fix_link_to_delete.rb

# Monkey-patch link_to (when called with method "delete") to use the authenticity token
# from the current page (in the #authenticity_token element), as opposed to hard-coding it.
# Rails' hard-coding breaks the app when using fragment caching because users get authenticity
# tokens that are old and/or not their own.
#
# To make the JavaScript less complicated, assumes that you have an element (like a DIV) 
# on the page with id="authenticity_token" that contains the authenticity token.
# It could also be adapted to use the authenticity token from the the csrf-token meta tag.
#
# See https://github.com/cheerful/freckle/issues/743

module ActionView
  module Helpers #:nodoc:
    module UrlHelper

    private

      def method_javascript_function(method, url = '', href = nil)
        action = (href && url.size > 0) ? "'#{url}'" : 'this.href'
        submit_function =
          "var f = document.createElement('form'); f.style.display = 'none'; " +
          "this.parentNode.appendChild(f); f.method = 'POST'; f.action = #{action};"
        unless method == :post
          submit_function << "var m = document.createElement('input'); m.setAttribute('type', 'hidden'); "
          submit_function << "m.setAttribute('name', '_method'); m.setAttribute('value', '#{method}'); f.appendChild(m);"
        end
        if protect_against_forgery?
          submit_function << "var s = document.createElement('input'); s.setAttribute('type', 'hidden'); "
          submit_function << "s.setAttribute('name', 'authenticity_token'); s.setAttribute('value', document.getElementById('authenticity_token').innerHTML); f.appendChild(s);"
        end
        submit_function << "f.submit();"
      end
    end
  end
end