I've published version 0.6 of my Python implementation of the PayPal NVP interface. You can download PayPal on Python here. The recent changes include:

• Fixed handling of dates. You can now use a Python datetime.date object anywhere the API calls for a date.
• Implemented recurring payments.
• Implemented Fraud Management Filters.
• Implement reference transactions.
• Changed the license from the Affero Public License to the GPL.

Enjoy! And, as usual, please feel free to contact me with any questions or issues.