expmail/sender.php

<?php

require_once 'config.php';
require_once 'Mail.class.php';
require_once 'Request.class.php';
require_once 'Response.class.php';

function handle_exception($e) {
    global $res;
    $res->handle_exception($e);
}

function handle_warning($errno, $errstr) {
    global $res;
    if ($res) { 
        $res->handle_warning($errstr);
    }
}

$res = new Response();

set_exception_handler("handle_exception");
set_error_handler("handle_warning", E_USER_WARNING);

$req = new Request(file_get_contents('php://input'));
$mail = Mail::FromRequest($req);
$mail->send();

$res->respond();