+Business::OnlinePayment::AuthorizeNet uses the ADC direct response method,
+and sends a username and password with every transaction. Therefore,
+Authorize.Net's referrer "security" is not necessary. In your Authorize.Net
+interface at https://secure.authorize.net/ make sure the list of allowable
+referers is blank. Alternatively, set the B<referer> field in the transaction
+content.
+