I’ve had to start using a Win98 machine at home which does not support Unicode.
After suffering from really painful problems via putty like unpredictable refresh problems in mutt/irssi and not knowing WTF you are in your editor vim after accidently using say ö, ä or å I decided to try downgrade on my server back to latin-1 (sudo dpkg-reconfigure locales).
Now my “unicoded” vim configuration still does not seem to understand ö, ä etc. but the results are lot more predictable. I don’t think I will touch my vimrc for now.
Unicode is pain. :/