"The problem is the RFID serial number used for collisions will not be encrypted as is required for communication, thus still allowing tracking."
In a CAST Forum presentation http://www.cast-forum.de/events/cast/2005/Biometr
The idea of using something printed in the passport to protect the access to the RF chip is called basic access control and is regarded as moderately secure by BSI (who claim that this protection is a European/German - don't remember exactly - idea). Even this basic protection is optional by ICAO standards and not implemented by many countries.
A a more advanced PKI based access control will be implemented by Germany in a second step (in 1-2 years, as far as I remember).
A method of solution is perfect if we can forsee from the start, and even prove, that following that method we shall attain our aim. -- Leibnitz