Honestly, there are about five or so pages worth of rules missing from the 40K rulebook. Actual rules, rather than a haphazard mixture of about three sentences of actual rules, several FAQ questions, ancient precedent, and assumption, to cover this situation isn't actually present.
The closest the rules come to covering the situation is one the FAQ answer stating that area effect psychic powers are measured from the vehicle's hull, so presumably one can measure to the hull for the psyker model in that situation. For psychic shooting attacks, the range and line of sight for shooting attacks use the fire point rather than the model, so by extension one would measure from the librarian to the fire point.
Fight for freedom against the undead Emporer!
Last edited by solkan; 03-19-10 at 12:51 AM.