Apple today has released the 10.5.6 update. The update includes many fixes and updates for Airport, Networking, MobileMe, and on and on. You can get it now via software update. See all the updates below:Read More
The Airport Extreme update has just been released. It is available now via Apple Update.
"This update is recommended for all Intel-based Macintosh computers running Mac OS 10.5.5 and resolves some issues with AirPort connections when roaming in large Wi-Fi networks."