I've upgraded to the latest version of this module from the oscommerce addons site (4th Feb 2010), and integrated with the Cardinal Centinel, but I'm still having problems with Maestro payments.
A customer using a Maestro card will be redirected to the 3D secure page, they enter their details, the message displays saying authentication was successful, but then they are redirected to the payment page saying there was a problem with their payment.
According to Paypal the error being returned is 12000: "Transaction is not compliant due to missing or invalid 3D-Secure authentication values".
I've been told the request to Paypal is missing the following variables:
Note that all other card types (Visa, Mastercard, etc.) are using 3D secure with no problems.
(p.s. thank you for developing this module!)