Setting up Instant Payment Notification (IPN)

<?php
$W 
= new WePay($access_token$token_secret);

$group_id apc_fetch('group_id');
$cb $W->post("/group/callback/$group_id"
               array(
'callback_url'=>'http://progphp.com/cb.php'));
print_r($cb);

// Get a list of callbacks for a group
$cbs $W->get("/group/callback_list/$group_id");
print_r($cbs);