this works in Rails 2, but not in Rails 3.

error.txt

NoMethodError: undefined method `_run_before_destroy_callbacks'

ticket.rb

class Ticket < ActiveRecord::Base
  def destroy
    return false if callback(:before_destroy) == false
    self.deleted_at = current_time_from_proper_timezone
    result = update_without_callbacks
    callback(:after_destroy)
    result
  end
end