I don't know if this information helps, but here in my Lenovo Y430 the keys work fine until just a bit after GDM starts. Maybe it's a module or daemon loaded by Upstart. I think it's worth to check it.
-- [Karmic] Brightness fn keys lost functionality (multiple laptops) https://bugs.launchpad.net/bugs/406515 You received this bug notification because you are a member of Ubuntu Desktop Bugs, which is subscribed to gnome-power-manager in ubuntu. -- desktop-bugs mailing list desktop-bugs@lists.ubuntu.com https://lists.ubuntu.com/mailman/listinfo/desktop-bugs