Try this (in Firefox): Tools->Options...->Privacy->Cookies Tab->View Cookies button.

In the list you must find your server domain name and cookies which are set by this server (you can use Search field at the top).

If you can't find your cookies than maybe you did't send cookies header correct (maybe you print them after \n\n?). You can use LiveHTTPHeader Extension with Firefox to see which info your browser get from server.