This port provides Cyrillic replacements for most of the standard
	/usr/X11R6/lib/X11/fonts/misc
and
	/usr/X11R6/lib/X11/fonts/75dpi
fonts.

You may want to make sure, the
	/usr/X11R6/lib/X11/fonts/cyr-rfx-koi8-o
is listed in your fontpath before those two paths.