Hi GA.
I would normally think so, I have a HTC Hermes/Cingular 8525 that seems pretty tolerant to charging however I want, whether it's on or off. But seeing these folks with the problems from just recieved C.C. and Buy Now (or whatever it is) IT's, I thought it might be prudent to not force the issue.

So the Nokias can be hooked up to the charger at anytime with impunity? Whether they're on or off? I've only hooked mine to the charger while it's off so far. And unhooked it before turning it on.
I like to err on the side of caution.
Thanks
K