Fizz Hit by Cho'Gath Scream When on Pole

Playing on Twisted Treeline as Fizz against Cho'Gath. I was on pole and he screamed, I took the silence and damage. Happened 6-8 times throughout the game. I'm fairly certain fizz should be untargetable on his pole; so I believe this to be a coding error that probably occurred when updating the script on the most recent patches? Perhaps not.

Don't have a screen shot but the bug is re-produceable.