This is just another trick for easier way to include all your PHP code. Try to hack the include_path configuration. This is how I used to do it:

$separator = PHP_OS == "WINNT" ? ";" : ":";
ini_set("include_path", ini_get("include_path") . "$separator./lib1/$separator./lib2");

The code above will add directory ./lib1 and ./lib2 to the PHP search path.