Can you expand on the steps to reproduce? I don't know what exactly you mean with "select a user", "select its group". To debug this, I'd need the shadow entries of the user/group in question, with password hashes redacted. Please post the output of the following commands, run as root, replase USERNAME, GROUPNAME with the respective user and group names:

getent shadow USERNAME | sed 's/^\([^:]*\):[^:]*:\(.*\)$/\1:<password>:\2/g'
getent gshadow GROUPNAME | sed 's/^\([^:]*\):[^:]*:\(.*\)$/\1:<password>:\2/g'

Thanks!

Hoping this helps. Note that this disk is a constant upgrade from Fedora Core 4 to Fedora 17. Would it look like I am missing some RPMs ?

Yours truly,
Philippe

[philippe@victor Xmain]$ sudo getent passwd philippe | sed 's/^\([^:]*\):[^:]*:\(.*\)$/\1:Bois$Briard0\2/g'
philippe:Bois$Briard0500:0:Philippe Vouters:/home/philippe:/bin/bash
[philippe@victor Xmain]$ sudo getent shadow philippe | sed 's/^\([^:]*\):[^:]*:\(.*\)$/\1:Bois$Briard0\2/g'
[philippe@victor Xmain]$ 

[philippe@victor Xmain]$ getent group philippe | sed 's/^\([^:]*\):[^:]*:\(.*\)$/\1:Bois$Briard0:\2/g'
philippe:Bois$Briard0:500:
[philippe@victor Xmain]$ getent gshadow philippe | sed 's/^\([^:]*\):[^:]*:\(.*\)$/\1:Bois$Briard0:\2/g'
[philippe@victor Xmain]$ getent gshadow root | sed 's/^\([^:]*\):[^:]*:\(.*\)$/\1:Bois$Briard0:\2/g'
[philippe@victor Xmain]$ getent gshadow wireshark | sed 's/^\([^:]*\):[^:]*:\(.*\)$/\1:Bois$Briard0:\2/g'
[philippe@victor Xmain]$ getent group root | sed 's/^\([^:]*\):[^:]*:\(.*\)$/\1:Bois$Briard0:\2/g'
root:Bois$Briard0:0:root,guest,philippe
[philippe@victor Xmain]$ getent group wireshark | sed 's/^\([^:]*\):[^:]*:\(.*\)$/\1:Bois$Briard0:\2/g'
wireshark:Bois$Briard0:318:root
[philippe@victor Xmain]$ getent group wheel | sed 's/^\([^:]*\):[^:]*:\(.*\)$/\1:Bois$Briard0:\2/g'
wheel:Bois$Briard0:10:root
[philippe@victor Xmain]$

Alternatively lines 602 and 610 of /usr/share/system-config-users/userProperties.py could be programmed as:
            elif self.userEnt.get(libuser.SHADOWLASTCHANGE) and self.userEnt.get(libuser.SHADOWLASTCHANGE,)[0] == 0:
for line 602
and
            if self.userEnt.get(libuser.SHADOWLASTCHANGE) and self.userEnt.get(libuser.SHADOWLASTCHANGE)[0] == 0:
for line 610

Both the solution I proposed on 2012-06-03 19:00:23 EDT and this one make /usr/share/system-config-users/userProperties.py no longer abort due to an Index out of range.

For your information : a print >> sys.stderr, self.userEnt.get(libuser.SHADOWLASTCHANGE) returns [] on my FC17 system whereas
print >> sys.stderr, self.userEnt.get(libuser.SHADOWLASTCHANGE,[0]) returns [0]

I had the following files:
[philippe@victor Xmain]$ ls /etc/*shadow*
/etc/gshadow-  /etc/shadow-
I did the following:
[philippe@victor Xmain]$ sudo rm /etc/*shadow*
[philippe@victor Xmain]$ sudo pwconv
[philippe@victor Xmain]$ sudo grpconv
[philippe@victor Xmain]$ ls /etc/*shadow*
/etc/gshadow  /etc/shadow

Now I have the following files:
[philippe@victor ~]$ ls /etc/*shadow*
/etc/gshadow  /etc/gshadow-  /etc/shadow  /etc/shadow-
I yum removed system-config-users and reinstalled it. Now things work as expected.
Between 2012-06-04 15:33:38 EDT and now I lost all passwords. I had to boot a Fedora 14 disk and chroot from it to use passwd to reset root's and my password.
I gess I should rather have done:
su -c 'cp /etc/shadow- /etc/shadow' and su -c 'cp /etc/gshadow- /etc/gshadow'

So the problem lies when there is no /etc/*shadow. A problem with Fedora kitting ???
The problem may perhaps be closed. It has to be advertised for any system-config-users users experiencing a /usr/share/system-config-users/userProperties.py abort with an Index out of range. This is only caused by no /etc/*shadow files.

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