As feisty now is in feature freeze mode (See https://wiki.ubuntu.com/FeistyReleaseSchedule) you'll need to wait until feisty + 1 :/
-- Dell Laptops don't talk to HAL about brightness correctly https://launchpad.net/bugs/43572 -- ubuntu-bugs mailing list ubuntu-bugs@lists.ubuntu.com https://lists.ubuntu.com/mailman/listinfo/ubuntu-bugs
