Description:
------------
The sample code to return 404 is incorrect for FastCGI mode. in FastCGI mode it would return 200, unless "header('Status: 404 File not found');" would be added. This means 'Status: *' is the third special-case header call besides 'HTTP/1.*' and 'Location: *'

Test script:
---------------
<?php
header('Status: 404 Dead beef.')
?>
This will return 404 for FastCGI request.

<?php
header('HTTP/1.0 404 Dead beef.')
?>
This will return 404 for CGI request.

You need to specify both to get code working under all circumstances.