Apple has released the 2.0.1 driver update for Airport for both Mac OS X and Classic Mac OS. The new version includes improved performance in a variety of ways. This from Apple:
This version of AirPort includes an updated driver for the AirPort Card and new firmware for the original AirPort Base Station (Graphite).
The updated AirPort driver improves robustness and prompts for a password when joining a password-protected "Computer to Computer" network.
The firmware update for the original base station (Graphite) provides better connections to some Internet service providers that use Point-to-Point Protocol over Ethernet (PPPoE).
The firmware update for the original base station (Graphite) allows Point-to-Point Protocol over Ethernet (PPPoE) connections with more Internet service providers, Use this firmware update only if you have the original AirPort Base Station (Graphite).
To update the base station firmware, open the AirPort Admin Utility and select your base station. Then click "Configure" and follow the onscreen instructions.
You can find more information and download links for the at Appleis Web site. The Mac OS X AirPort update is also available.