One thing you might want to try. We use a lot of FireFox for one good reason (at least), a plugin called livehttpheaders. It will show you all headers going in and out of the browser. That will help show what cookie headers are present.

To my knowledge a domain is not required to be set, however it should be remembered that the domain and path will default to the current value of hostname and the current script's path. So a cookie set from the script www.test.com/perl-bin/setters/cookies.pl will set the domain to 'www.test.com' and the path to '/setters/' requiring any script reading those cookies to be called from the same host and within that path. Try the FireFox plugin and see iof the headers are going through.

Edit by castaway: Closed small tag in signature