Tested with RHL 8.0 and using sv_SE.UTF-8. redhat-config-xfree86 uses the wrong decimal character (point instead of comma) in the monitor frequencies section, both in input and display (see screenshot). This locale's decimal character is comma.
Created attachment 79720 [details] Screenshot showing use of wrong decimal characters
This is an unfortunate problem with python. The python environment fails if you change the numeric locale, so pygtk2 automatically sets it to C.
Should I file a bug report against python?
pygtk does: /* set the LC_NUMERIC locale back to "C", as Python requires that * it be set that way. */ setlocale(LC_NUMERIC, "C"); I'm not sure this can be fixed, but maybe it can.
Easiest would be to just ask jamesh if this is fixable.