Apple has released AirPort Software 3.1.1, which includes version 5.1.1 of the AirPort Extreme base station firmware. According to the release notes, the update “is recommended for all users with an AirPort Extreme enabled computer or an AirPort Extreme base station.” However, the other improvements listed are identical to those provided with the AirPort 3.1 release. Version 3.1.1 is available via the Mac OS X Software Update preference pane.