ctrl+up|down don't change screen brightness any more
i had slackware 13.0 on my dell vostro 1320 and it was all good, but since the upgrade to 13.1 i cannot change the screen brightness with ctrl+up and ctrl+down keys...
i'm not even sure how to start with this problem. from what i understand these keys 'call' a bios function...? so that would mean that some kernel module is not being loaded?
or has the desktop environment lost the key mappings and that is causing my trouble?
any ideas would be appreciated. thanks.