module ActiveSupport::CoreExtensions::Date::Behavior

def acts_like_date?
  true
end

def freeze #:nodoc:
  self.class.private_instance_methods(false).each do |m|
    if m.to_s =~ /\A__\d+__\Z/
      instance_variable_set(:"@#{m}", [send(m)])
    end
  end
  super
end