checkout_controller_decorator.rb

gistfile1.rb

Spree::CheckoutController.class_eval do

  def before_address
    # If the user has a default address, a callback takes care of setting
    # that; but if he doesn't, we need to build an empty one here.
    # Regardless of checkout steps, build a shipping address 

    @order.bill_address ||= Spree::Address.build_default
    @order.ship_address ||= Spree::Address.build_default 
  end

end