You need to include the file containing the class Say
you added via addAPIClass
method. Your index file should be something like below
require_once 'restler/restler.php';
require_once 'classes/lbs.php';
require_once 'classes/say.php';
$r = new Restler();
$r->addAPIClass('LBS');
$r->addAPIClass('Say');
$r->handle();