Wait a minute! Ricky already figured out how to get Hal to say -Duh!-
It's a valid response!
But IMHO, the test should not be to trick humans into believing they are talking to a human but rather to allow the machine to respond as a machine that has SELF-AWARENESS of its virtual reality.
Judges would then have to figure out which entrant was in fact NOT a machine instead of the other way around.
I believe the outcome would be quite different and might show a larger proportion of judges would be unable to judge the difference between a human acting as a machine and a machine just being itself.