blank screen doesn't turn of LCD light

I've got FC2 on a Dell D400 laptop, and have set the screen saver
to blank screen only; and although the screen goes blank, the
LCD backlight remains on. I can manuallly turn the light off with

    xset dpms force off

Is there any way I can get this to happen automatically?

Dave.

-- 
Wesley Crusher gets beaten up by his classmates for being a smarmy git,
and consequently has a go at making some friends of his own age for a
change.
    -- Things That Never Happen in "Star Trek" #18