not overriding new properly

locale.rb

class Locale

  # must provide session and request options
  def self.new(options = {})
    initialize_region(options) || NullLocale.new
  end

  # return the region object associated with this Locale
  def region_name
    @region.name
  end

  def region_id
    @region.id
  end

  def valid?
    true
  end

  private
  def self.initialize_region(options = {})
    raise ArgumentError, 'No session provided' if options[:session].nil?
    raise ArgumentError, 'No request provided' if options[:request].nil?

    @region = case
              when Subdomain.matches?(options[:request])
                region = Region.find_by_subdomain(options[:request].subdomain)
                options[:session][:region_id] = region.id if region.present?
                region # @region = region
              else
                Region.find_by_id(options[:session][:region_id])
              end
  end

end

class NullLocale < Locale

  def region_name
    ''
  end

  def region_id
    nil
  end

  def valid
    false
  end

end