Dear Stefan, I've installed Karmic from new and the bringhtness problem persists. But now I can't find the menu.lst file to set the boot option. Before installing, I had tried to go back to the last patched kernel version with dkpg. I successfully changed the kernel, but the brightness control didn't come back. I'm attaching the dmesg output. My eyes will thank your efforts.
** Attachment added: "dmesg.log" http://launchpadlibrarian.net/35786418/dmesg.log -- Acer: Cannot change brightness with 2.6.27-11+ kernel https://bugs.launchpad.net/bugs/333386 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