"locked" has never meant "unclockable".
Locked just means the "multiplier" on the cpu is locked.
That sort of limits you to raising the fsb (front side bus) in order to overclock.
I am sure there are ways to unlock it anyway, and possibly motherboards that unlock it for you.
Then there are adapters available like
this one that evidently unlock it for you.
So locked or unlocked is only referring to the mulitplier...NOT the overall speed of the cpu.
Check into some overclocking sites and they will have tons of info on this stuff.
JP