And there is, of course, the slap-my-forehead-and-say-d'oh response if the answer to the following is yes...

Are you trying to access the cookie in the same script invocation that sets the cookie?

Only cookies sent from the browser are stored in the $ENV{'HTTP_COOKIE'} / $q->cookie() object, so if you've just set the cookie, it's not available in that object until the browser next calls the script.

cLive ;-)