Authorize.net not informing of errors

[Scott Ackerman]

I have a Joomla 1.015 installation with VM 1.1.2. Using Authorize.net with "Show response codes for failed transactions" set to 'yes'. However when a credit card transaction fails for any reason, the screen simply refreshes and there is no indication that there was a problem. Non-failed transactions are processed just fine. URL http://www.modelrollercoasterhq.com. PHP 5.1.6 and MySQL 5.027 on a FC6 box.