yes it is.

short answer:
-open xterm
-sudo gainroot
- echo 2 > /sys/class/backlight/acx565akm/brightness
- voila! you are done (its and expression, dont type this)

the default 1 level is 7 in brightness.

the new value its a bit darker than the keyboard leds.

an easy solution? no :P its easy enough for me. i dont know other way

ps: brightness 1 is black. dont try it if you dont know how to get out