A new update is available for Fedora Core - Fedora Core 4 Update: system-config-users-1.2.39-0.fc4.1. Here the announcement:

Fedora Update Notification
FEDORA-2005-912
2005-09-29
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Product : Fedora Core 4
Name : system-config-users
Version : 1.2.39
Release : 0.fc4.1
Summary : A graphical interface for administering users and groups
Description :
system-config-users is a graphical utility for administrating
users and groups. It depends on the libuser library.

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Update Information:

Barring problems I plan to make this final within a week.
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* Fri Sep 23 2005 Nils Philippsen <nphilipp@redhat.com> - 1.2.39
- require rhpl (#168921)

* Fri Jun 10 2005 Nils Philippsen <nphilipp@redhat.com>
- allow punctation in user names (#141273)


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This update can be downloaded from:
http://download.fedora.redhat.com/pub/fedora/linux/core/updates/4/

fb0aaf4cbfd5bf9f6784edceb3a2fcb2 SRPMS/system-config-users-1.2.39-0.fc4.1.src.rpm
63d42e6c95b2547bf7f9da95d774d522 x86_64/system-config-users-1.2.39-0.fc4.1.noarch.rpm
63d42e6c95b2547bf7f9da95d774d522 i386/system-config-users-1.2.39-0.fc4.1.noarch.rpm

This update can also be installed with the Update Agent; you can
launch the Update Agent with the 'up2date' command.