Drupal 6 Query String Block?

I need to display a block on a specific query string URL (i.e. www.mysite.com/civicrm/event/register?reset=1&id=1089)

I found this code which I believe is for D7, because it WSODs the site when used:

<?php
$match = FALSE;
if (current_path() == 'civicrm/event/register' && isset($_GET['id']) && $_GET['id'] == 1089) { $match = TRUE; }
return $match;
?>

https://www.drupal.org/project/block_query is a no go, also for D7

Can anyone guide me on how to format the above Block PHP code for D6?

Thank you!