# File lib/openid/consumer.rb, line 617
    def gen_token(consumer_id, server_id, server_url)
      timestamp = Time.now.to_i.to_s
      joined = [timestamp, consumer_id, server_id, server_url].join("\x00")
      sig = OpenID::Util.hmac_sha1(@store.get_auth_key, joined)
      OpenID::Util.to_base64(sig+joined)
    end