Got this message from PayPal:
please be aware that as of 21 January 2010, you will not be able to process Maestro payments through UK Website Payments Pro – Direct Credit Card Payments without 3-D Secure technology. This is due to MasterCard Compliance rules.
It is important that before this date you remove the Maestro option as a card type on your Card deposit page. This will ensure you keep declines to a minimum, maintain conversion and provide a good experience for your customers.
Want to continue to process Maestro transactions?
If you want to continue processing Maestro transactions after 21 January 2010, you must implement 3-D Secure. PayPal does not charge for the use of 3-D Secure and nor does Cardinal Commerce, our chosen 3-D Secure technology provider.