look for a file which is called by xmodmap
mine is called userdefined.xmodmap
and is located in /etc/X11/kb
it maps keycodes to symbols (e.g. characters, comma, plus, minus, asterisk)
to find out keycodes run xev and press some keys
to find out the correspondent symbols (e.g. period, slash, at, equal, less, greater etc.) simply try or have a look at existing "xmodmap"-files
regards
seb