Comment 2 for bug 182421

For anybody else having this annoying problem here is the way I usually help myself.

* open terminal
* type n - TAB, bash-completion will respond with a list of command starting with n
* copy numlockx and paste it into the console twice with a space in between
* delete everything but the o from the second occurrence and append with ff (the f key is not affected)
* you now have "numlockx off" on the console, hit enter and numlock will turn off

There are of course more elegant methods, but this should work every time in case you have no other options

HTH