Fix brightness issue in Ubuntu 10.04 Lucid Lynx?

I've upgraded from 32-bit ubuntu 9.10 karmic koala to 32 bit 10.04 lucid lynx and my brightness control does not work at all. I am running on a toshiba satellite a305-s6858, 4gb ddr2, 2 ghz intel core 2 duo t5750 with an integrated intel gma x3100 gfx card. The function key plus f6/f7 used to work for adjusting brightness in karmic but not in lucid. even the brightness control panel won't work. i also dual boot the system with windows 7 ultimate 64 bit and the brightness works fine on there so it's not anything hardware. is there and terminal code to type in to fix this bug?