I would think that any mail server would allow forwarding. Well anyway, I believe that include/func/func.order.php would control sending the mail.
I see this around line 1438 in 4.4.X
Code:
if ($admin_notify) {
// Notify orders department by email
$mail_smarty->assign('show_order_details', 'Y');
func_send_mail(
$config['Company']['orders_department'],
'mail/' . $prefix . 'order_notification_subj.tpl',
'mail/order_notification_admin.tpl',
$userinfo['email'],
true,
true
);
$mail_smarty->assign('show_order_details', '');