X11/xterm Unicode woes

[Andrew Pantyukhin]

About a month ago UTF-8 locale stopped working in my xterm.

I fail to find comprehensive documentation on fonts in X11
and therefore I fail to fully understand and trace the problem.
I'll be most grateful if somebody leads me to a source of
fine docs, but I'm really full of doubt after much googling.
README.fonts and manpages are helpful in that they shed
some light on how to tune a working setup, but I can't learn
the way fonts work from them.

I don't have any fontpaths defined in xorg.conf, I though it
wasn't a problem. xfontsel have always shown some 12000
matches, many of which were unicode. Now I try xfontsel -
and it only shows matches in default fontpaths until I run
xset fp+ on the rest of them. Nevertheless, xterm fails to display
russian fonts, and displays only a fraction of the Chinese and
Japanese it used to display.

A couple of weeks ago I installed a fresh FreeBSD system on
another computer - and everything works great there. But my
issue is not a singleton, I stumble upon it both at work and at
home. I don't use russian in console that much, but I still do
occasionally. I have to support file servers with UTF-8 filenames.
And I start experiencing some obscure problems with encodings
(like, for example, mldonkey is totally freaked out) on other
FreeBSD systems, so I really want to sort this out.

Thanks!