I have never seen that before (the X3 ending).
neat!
(edit: "she appears again for a brief scene, where it appears that Xavier has transferred his mind into the body of the patient, following his physical body being disintegrated by the Phoenix persona that inhabits Jean Grey. In the director's commentary for the movie's DVD, it is revealed that this patient is, in fact, the identical twin of Charles Xavier, whose mind had been destroyed before birth by the power of Charles' mutation. Thus it is that Charles' voice is used and Moira instantly recognizes him.")
hmmmm..