I have finished development of a PHP class for managing Authorize.net Automatic Recurring Billing (ARB) transactions. The code and description have been published on the PHP Classes website.

Direct link: http://www.phpclasses.org/browse/package/4666.html

The intended use for this class is to handle the addition, modification, and removal of recurring, subscription-based transactions through the Authorize.net payment gateway.

This class requires PHP 5