Session handling for http clients

I'm trying to make two or more http request in a row to a
session-enabled Prolog web api from a client implemented by means of
http_open/3. Roghly like so:

  ...
  http_open('http://domain.org/first', Stream1, []),
  ...
  http_open('http://domain.org/second', Stream2, []),
  ...

The thing is that I need the two request to be part of the same http
session. Just making the requests doesn't ensure that they are. How
can I solve this?

Cliopatria has a file sesame_client.pl that seems to do what I want,
but there's a lot of code there and it got me lost. :-(

Thanks,
Torbjörn

-- 
Torbjörn Lager
Professor of General and Computational Linguistics
Department of Philosophy, Linguistics and Theory of Science
University of Gothenburg
Box 200, SE-405 30 Gothenburg, Sweden
Phone: +46317864962