Hide Notifications fieldset

On my site I need to prevent everyone from unsubscribing, so there is no need to display Notifications box under the comments. How can I hide it completely? Since the fieldset does not have id or class, I guess I need to use a function in template.php, something like:

<?
function phptemplate_notifications_info () {
return '';
}
?>

but which one exactly, since phptemplate_notifications_info does not work?