running scim input method with built-in fvwm

1) edit ~/.xsession
export LC_CTYPE=en_US.UTF-8
export XMODIFIERS=@im=scim
export GTK_IM_MODULE="scim"
scim -d&
/usr/X11R6/bin/xterm &
exec dbus-launch /usr/X11R6/bin/fvwm

2) Exit and login again via xdm.