A new beta build of Service Pack 1 for Windows Server 2003 will be made available later today. The build, 1137, will be up for grabs for both x86 and AMD64 systems.
New Functionality Included in Service Pack 1:
The Security Configuration Wizard - The Security Configuration Wizard is included with SP1 for the Windows Server 2003 family. You can use the wizard to create, edit, or apply a security policy for a computer or group of similarly configured computers.
IIS 6.0 Performance - "Kernel-mode" (as differentiated from "user-mode") improves SSL performance because it moves encryption and decryption operations to the kernel.
Internet Connection Firewall for IPv6 - Internet Connection Firewall for IPv6 is included.
32-bit applications running on 64-bit platforms - The performance of 32-bit applications running on 64-bit Windows operating systems (WOW64) is improved because WOW64 now uses the Intel IA32 EL driver.
The above is not a complete list of new features included in SP1. For a full list and more information view the readme file included with the build.
Note: If you are running a previously released Service Pack 1 build (eg. 1039-2, 1069), you must uninstall it first before attempting to install build 1137.