WPA added to Apple Extreme 802.11g equipment: It's been a long-awaited moment, but Apple has finally shipped the AirPort 3.2 upgrade which includes Wi-Fi Protected Access (WPA) support to the AirPort Extreme Base Station and AirPort Extreme Card. That's right folks, if you've got plain old AirPort cards and AirPort Base Stations, you're out of luck. I'll try to get more information out of Apple about their plans for older devices. The download is currently only available through the Software Update preference pane.
According to the WPA standard, older devices should be able to connect to a WPA-enabled network using a WEP key derived in some fashion from the WPA key. In this release, at least, Apple states categorically that devices without WPA support cannot connect. We'll see how this evolves over time as it's in opposition to the principles of WPA and 802.11i, the larger standard that's a sort of superset of WPA and is due to be finalized next year.