Comment 3 for bug 63104

Same here with Edgy Final (updated via Web from Beta).
After a bit of detective work, I've found that the LED stops responding when the /etc/init.d/keyboard-setup script runs as part of rcS.d. The package which owns this script is console-setup, and the script it calls is /bin/setupcon which is owned by the same package (console-setup). If I disable /etc/init.d/keyboard-setup the LED stops responding later in the boot process when /etc/init.d/console-setup is run.

NEW INFO: Caps seems to be acting as a Shift Lock (Sticky Shift), not Caps Lock - I'm getting : rather than ;, @ rather than ' etc (British keyboard). Maybe Pascal De Vuyst, eantoranz or some other victim could verify this if they're still struggling (and if not, please share how you fixed it!). If the Caps key isn't even working as Caps Lock, then maybe this explains the LED not functioning correctly.