Running Ubuntu 9.10

So I installed libpam-fprint, fprint-demo, libfprint-dev, etc..

Enrolled fingerprint..

Added the following 2 lines to /etc/pam.d/common-auth

auth sufficient
auth required nullok_secure
Fingerprint reader does work, however I am being asked for a password first on login and sudo, and then a fingerprint (both).

I'd like this to be reversed, where I am asked for a fingerprint, and failing that, a password.

Where did I go wrong?