Sonic IPN v1.2 – Paypal IPN Redirector WordPress Plugin
Date: 6 January 2014 | Posted by: unic
The PayPal IPN is an important tool for integrating with 3rd party systems, such as membership sites, ticketing systems, and various fulfillment systems.
The problem with the PayPal IPN is that you can only have one IPN forwarding URL.
See full article