First, here is some info:

[root@matador /etc]# rpm -qi control-panel
Name        : control-panel               Distribution: Red Hat Linux
VanderbiltVersion     : 2.6                               Vendor: Red Hat
Software
Release     : 1                             Build Date: Tue Dec 10
21:41:45 1996Install date: Thu Apr 10 22:46:42 1997      Build Host:
porky.redhat.com
Group       : Utilities/System              Source RPM:
control-panel-2.6-1.src.rpm
Size        : 178835
Summary     : Red Hat Control Panel

[root@matador /etc]# rpm -qi shadow-utils
Name        : shadow-utils                Distribution: Red Hat Linux
Colgate
Version     : 960530                            Vendor: Red Hat Software
Release     : 6                             Build Date: Thu Sep 05
23:47:04 1996Install date: Thu Jun 05 10:24:43 1997      Build Host:
porky.redhat.com
Group       : Utilities/System              Source RPM:
shadow-utils-960530-6.src.rpm
Size        : 74466
Summary     : Shadow password file utilities for Linux

[root@matador /etc]# cat /etc/redhat-release
release 4.1 (Vanderbilt)

And the bug:

[root@matador /etc]# ls -l /etc/shadow
-rw-------   1 root     root          693 Jun 10 11:19 /etc/shadow

Now I start X, run user and group configuration in control-panel.
I change some data then save and quit.

[root@matador /etc]# ls -l shadow
-rw-r--r--   1 root     root          693 Jun 10 11:19 shadow