ROFL, I spent more than 6 hours last night (or was it this morning) searching every possible inch of Act4 that I can reach and nada... I even went so far as dragging nearly every movable item into that room hoping for a BINGO!!!
The request from the Summoning Instructor is... ummm... vague. He may have just told me to "Find something that I am thinking of, and do it now".
THe problem is that now I don't know if I am being defeated by a self-imposed broken quest (after installing patch 1.42 I loaded my 1.41 game and immediately saved it again under 1.42, hoping that would be fine).
Good Luck. Too bad there is no multi-player or we could search together <img src="/ubbthreads/images/graemlins/smile.gif" alt="" />