I was playing on one of my alternate characters (4/9/2011, 1:35am CDT) Oclesia Rastova. Anyway, I had been playing her to rank 14 Pugilist, and for the first time equipped her with a cane to level Conjurer. Upon trying to cast any spell at all, I could not toggle AoE with "Z" as the green icon the indicates whether AoE is on or off would not appear. I logged off and switched to another character to check, and on both Thaumaturge and Conjurer, the AoE toggle appeared. I switched back to Oclesia, and the toggle still would not appear for her.

I remedied the situation by resetting my widgets, at which point it did finally appear, and allowed me to toggle. This should be fixed as soon as possible though, as it could cause many new players to not realize they can toggle AoE.