[K12OSN] I've done a mess

[Antonello]

Well, I've been playing a bit with my k12ltsp (FC1), and I surely made
some disaster.
When I choose from kde menu the add/remove-apps option (running as root)
the program does not sart at all.
I tried in a console and redhat-config-packages returns this message:

(process:3382): Gtk-WARNING **: Locale not supported by C library.
        Using the fallback 'C' locale.
Traceback (most recent call last):
  File "/usr/share/redhat-config-packages/MainWindow.py", line 130, in ?
    locale.setlocale(locale.LC_ALL,"")
  File "/usr/lib/python2.2/locale.py", line 381, in setlocale
    return _setlocale(category, locale)
locale.Error: locale setting not supported

that's definitely too much for a newbie like me.
Could you give me a hint, please?

tia
Antonello