OK, so I have an adult shop I am working on. I have a script that SEEMS to work, just not with zen cart... haha. I think for some reason zen-cart isn't allowing a separate session or something.

the zc store is located like in the following directory:
www.domain.com/store

in the root folder (store) I have the following .php file (verify.php)
PHP Code:
<?php 
session_start(); 
if ($_REQUEST["over18"] == 1) { 
    $_SESSION["over18"] = 1; 
    header("Location: " . $_REQUEST["redirect"]); 
} 
?> 
<html> 
    <head> 
        <title>Verify Your Age</title> 
    </head> 
    <body> 
        <a href="/store/verify.php?over18=1&redirect=<?php echo $_REQUEST["redirect"]; ?>">I am over 18</a> |  
        <a href="http://www.google.com/">Get me out of here!</a> 
    </body> 
</html>
Then I have the following in my includes/application_top.php file at the very end:
PHP Code:
<?php 
session_start();
if ($_SESSION["over18"] !=1) {
    header("Location: /store/verify.php?redirect=" . $_SERVER['PHP_SELF']); 
} 
?>
I get the verify.php page to come up, but when clicking "I am over 18". It simply redirects back to the same page... What am I doing wrong? Please note that the script is in the application_top.php file so that this check populates whatever page the customer enters from, not just the homepage...