Mac OS X Server 10.2.1 (Build 6D52)

is available for download via the Software Update preference panel or directly. According to this Apple KBase article, v10.2.1 Server provides in addition to the 10.2.1 client update these enhancements:

File Services

* Resolves an issue with the SMB mount command.

Password Server

* Allows Open Directory Password Server to be located on a secondary or standalone server.
* Improves Password Server database integrity.

Installation

* Works better with remote Installation on ports other than the built-in (en0).

Workgroup Manager

* Improvements in Workgroup Manager user creation <cancel> handling.

Open Directory

* Addresses an issue with Open Directory LDAP server, preventing automatic discovery of the directory using DHCP.

Network Image Utility

* Changing active NetBoot images in the Network Image Utility no longer requires you to restart.
* Resolves an issue in which the Network Image Utility creates images with incorrect permissions.

Networking and Mail Enhancements

* Addresses a situation in which certain Internet service providers (ISPs) may not accept outgoing email (SMTP) from computers using NAT and a ".local" hostname (which may be assigned by Rendezvous).
* Improves Mac OS X Server performance in heavy AFP client load situations.
* Improves Mac OS X Server reliability when a Mac OS 9 client attempts a scheduled AFP connection.

Printing Enhancements

* Improves compatibility with HP LaserJet 4V and HP LaserJet 4MV printers.
* Reduces occurrences of a potential "busy; source EIO (ATALK)" alert message when printing using AppleTalk via CUPS.
* Addresses an issue in with printing via CUPS in which the second queued print job would automatically start if the first print job was stopped.
* Includes various other CUPS printing-related enhancements.
* Fixed condition in Print Server which could lead to over utilization of CPU cycles.

Other Enhancements

* Addresses a potential issue in which a USB keyboard or mouse is not recognized nor able to wake the computer, if they are connected to or disconnected from an external USB hub, while the computer is in sleep.
* Addresses a potential issue in which Mac Help may not be available following an erase-installation.
* Addresses various potential kernel panic situations.

We installed it on a G4 Cube with no problem.