session_destroy() in 4.0.2...do they work?

I use session_destroy on a page when a visitor leaves a certain area. When they leave the session is still active. I have tried it on two different platforms, the results are a little different, but either way the session is still there. Here's the platforms: Platform 1: Linux 2.2.16 (I think) Apache 1.3.12 PHP 4.0.3pl1 Result: No errors, but session is still active Platform 2: Win 98SE Xitami v2.4d6 PHP 4.0.2 Result: Session object destruction failed.... Here's the code snippet in question //Track Session session_start(); if ((!$PHPSESSID) || (!$item_count_total)) { session_register("item_count_total"); } if (!$item_count_total) { $item_count_total = "0"; } //Closes Session session_destroy(); session_unregister("item_count_total"); I have looked at messages where several people talk about this, and the response is typically to use cookies. I really don't want to to that. No one ever seems to know why it doesn't work. Any ideas on what the problem is?