Friendship create action

I am trying to create a friendship system. There is a post at
http://stackoverflow.com/questions/5612736/how-to-implement-a-friendship-model-in-rails-3-for-a-social-networking-applicati
Which seem great but the create action doesn't work. How can it work
here what I have

Controller
  #Send a friendship request
  def create
    Friendships.request(@customer, @friend)
  end

Model
  # Record a pending friend request.
  def self.request(customer, friend)
    unless customer == friend or Friendship.exists?(customer, friend)
      transaction do
  create(:customer => customer, :friend => friend, :status => 'pending')
  create(:customer => friend, :friend => customer, :status =>
'requested')
      end
    end
  end

Here how I call it in my view and i think this is where the issue is
      <%= link_to "Request friendship with #{customer.first_name}",
    { :controller => "friendships", :action => "create",
  :id => customer.id },
  :confirm =>
  "Send friend request to #{customer.incomplete_name}?" %>
      <% end %>

Now the tutorial is old an i am wondering if the way i am calling it his
the proper way.
Thanks in advance