Phanx, as always your code is lovely and concise.
Since I no longer need to point anything else out, since Phanx explained so well, I want to tell the OP that he forgot the hunter pet version, Ancient Hysteria. Spell ID is 90355.
Code:
[(GetSpellInfo(90355))] = false, -- Ancient Hysteria
ETA: And beaten to the punch again. Really should stop doing things in the following order: open thread, go afk, return and begin to type.
Edit again: I just noticed all of us joined the site in 2006. That's a slightly strange coincidence.