Apple has released Mac OS X Server v10.6.4 Update (v.1.1). The 615.34MB update is recommended for all servers currently running Snow Leopard Server version 10.6. It includes Safari 5 and general operating system fixes that enhance the stability, compatibility and security of your server, as well as specific fixes for:
° CalDAV querying of email addresses with Active Directory and Open Directory servers;
° Stability and reliability accessing Wiki Server pages;
° The ability to view movies on Wiki Server with Safari on iPad;
° Accessing publicly accessible Wikis when logged in to the Wiki Server;
° Listing blogs on Wiki Server;
° Vacation mail notices that span across multiple days;
° Updates from Software Update Server viewable by clients;
° Stability and reliability to Software Update Server synchronization;
° Downloading of software updates by Software Update Server;
° Creating NetInstall images which include iLife updater packages;
° Addressing of issues copying, renaming, or deleting files on SMB file servers;
° Improving the reliability of VPN connections.
Mac OS X Server v10.6.4 Update (v.1.1) requires Mac OS X 10.6.3 Server or higher. You can find more info at http://support.apple.com/kb/DL1050 .