Problem. When running the AirPort Utility on Apple Leopard OS 10.5, a message appears stating, “A newer version (5.3.1) of AirPort Utility is available. Click Update… to launch Software Update and quit AirPort Utility.” When Software Update runs, it reports, “Your software is up to date. Software Update doesn’t have any new software for your computer at this time.”
Solution. Go to the Apple website and find the Apple Airport Utility 5.3.1 version dated March 11, 2008. As of March 12 at 4:02 AM, the Software Update utility is unaware that this update exists.