# File lib/openid/util.rb, line 132
    def Util.sign_reply(reply, key, signed_fields)
      token = []
      signed_fields.each do |sf|
        token << [sf+":"+reply["openid."+sf]+"\n"]
      end
      text = token.join("")
      signed = Util.to_base64(Util.hmac_sha1(key, text))
      return [signed_fields.join(","), signed]
    end