Just have a page - like
wp-logout.php - that runs
or better yet,
wp_logout() (wp manual)
Albeit, I should offer an alternative to completely disabling that...
You could, for example, have a whitelist of IP's - and in your
header("Location: http://yourpage.com"); exit();
Alternatively, you could just store the whitelist in an array that comes
right before that...
$whitelist = array("123.456.789.100", "184.108.40.206");