Rails - server to use public IP

require 'rails/commands/server'
require 'socket'

module Rails
  class Server
    alias :default_options_alias :default_options
    def default_options
        ip_addr_list = Socket.ip_address_list
        #puts ip_addr_list.inspect
        if ip_addr_list.count >= 2
          ip = ip_addr_list[1].ip_address
        else
          ip = ip_addr_list[0].ip_address
        end

      default_options_alias.merge!(:Host => ip)
    end    
  end
end

This may have some inherent issues depending on the system, but worked on a couple of my machines.