Version:           3.4 (using KDE 3.5.0, compiled sources)
Compiler:          gcc version 3.4.4 20050721 (Red Hat 3.4.4-2)
OS:                Linux (i686) release 2.6.9-1.667smp

I try to compare two files in KOI8-R codepage. First, I cannot find KOI8-R in encoding list. It's annoying but is not fatal, I use koi8-u. When main window is appeared, differences is shown as umlauts, not Cyrillic. I look program output:
...
kompare: Encoding: koi8-u
...
kompare:  Trying to find DEFAULT in /usr/share/i18n/charmaps
kompare (libs): "LANG=C" "diff" "-U" "3" "-H" "-d" "-r" "-N" "--" "'/home/cas/22'" "'/home/cas/33'"

Why DEFAULT? I select koi8-u! 
If I manually run this command, output has koi8-r characters. But why Kompare doesn't show differences in the main window in appropriate encoding?