are you trying to only show a pages content if they are a logged in user?
Use PHP
Here is an example
PHP Code:
<html>
<body>
<?php
$curdir = getcwd ();
chdir('/path/to/your/account/public_html/');
require_once('/path/to/your/account/public_html/global.php');
chdir ($curdir);
if ($vbulletin->userinfo['userid']!=0) {
echo "<p>Welcome <b>";
echo $vbulletin->userinfo['username'];
echo "</b></p>";
?>
<p>CONTENT TO SHOW WHEN LOGGED IN</p>
<?php
} else {
?>
<p>Please <a href="./path/to/forum/register.php">register</a> or login to view this content.</p>
<?php
}
?>
</body>
</html>
yourfile.php
the domains would have to be on the same server though.