[GRASSLIST:5858] NVIZ error

Greetings all,
Whenever I try to change any of the sliders in NVIZ, I an eeror. For example, when I change the zexag slider I get the message:
can't read "Priv(.top2.panelarea.panels.main.midf.zexag.scale,relief)": no such element in array
can't read "Priv(.top2.panelarea.panels.main.midf.zexag.scale,relief)": no such element in array
    while executing
"$w configure -sliderrelief $Priv($w,relief)"
    (procedure "tk::ScaleEndDrag" line 4)
    invoked from within
"tk::ScaleEndDrag .top2.panelarea.panels.main.midf.zexag.scale"
    (command bound to event)

I'm using grass6.0.beta2 (same thing happened with beta1) under SuSE 9.0. Everything seemed to compile correctly. Any suggestions would be greatly appreciated.
Regards,
Andy Bernat