I have this problem as well. The brightness applet will display that it has changed the brightness, however nothing changes. I can add that, for me at least, this appears to have something to do with the drivers. Setting brightness worked fine with the open source, but when I switched to fglrx it stopped working.
Toshiba L305 w/ Radeon HD 3100 card. -- Cannot adjust brightness in Lucid Lynx https://bugs.launchpad.net/bugs/555122 You received this bug notification because you are a member of Ubuntu Bugs, which is subscribed to Ubuntu. -- ubuntu-bugs mailing list ubuntu-bugs@lists.ubuntu.com https://lists.ubuntu.com/mailman/listinfo/ubuntu-bugs