Rails - Mar 2006 - ActionController::Verification problem

Hello,

I have a subscriptions model and a ''new'' action in
subscriptions
controller to create new subscription. Also, I have a
''thankyou'' view,
which I want to display only if user is just subscribed. So I want to
block access to http://localhost/subscriptions/thankyou action with a 
 verify filter. Here is my code:

class SubscriptionsController < ApplicationController
  verify :only => :thankyou,
          :flash => :subscription,
	  :redirect_to => :index

    def index
      # new
      # render :action => ''new''
    end

  def thankyou
  end
end

I get

SystemStackError in Subscriptions#thankyou
stack level too deep

error.

Can''t figure out, what is wrong. I suppose an eternal loop might be a
cause, but I don''t see any in this simple code. Any hints?

Leo