..."delivers a number of security enhancements and is recommended for all Macintosh users. This update includes the following components:
Windows File Sharing.
Additionally, Security Update 2003-12-19 has been incorporated into this security update. Those components are:
ASN.1 Decoding for PKI
AirPort Software Update!
"This software update provides improved AirPort wireless networking software, and is recommended for all users with an AirPort Extreme and AirPort enabled computer or an AirPort Extreme base station.
New AirPort Extreme Features:
This software provides support for the Wi-Fi Protected Access™ (WPA) specification for the AirPort Extreme base station and AirPort Extreme and AirPort clients. Please see AirPort Help for more information on WPA. Also included in this release is v5.3 of the AirPort Extreme base station firmware. Instructions for updating the base station firmware can also be found in AirPort Help."