I have a script containing the following:

<?php
include 'person.class.inc';
$CLperson = new Person;
?>

File person.class.inc contains the following:
<?php
require_once 'std.table.class.inc';
class Person extends Default_Table
{
   ...
}
?>

File std.table.class.inc contains the following:
<?php
class Default Table
{
include 'test.inc';
}
?>

When I run it I get the following error:

"Parse error: parse error, unexpected T_INCLUDE, expecting T_OLD_FUNCTION or T_FUNCTION or T_VAR or '}' in F:\Apache2\HTDOCS\XAMPLE\std.table.class.inc on line 4"

The only variation that actually works is:-

$result = include 'test.inc';

BTW, I am using the ISAPI version of PHP under Apache 2.0.44