deidaras a dude, nuff said.

but that vioce will most likely be changed. deidara first fully appeared in the manga shortly before that episode. animation takes a long ass time to do even if you are using a cost effect korean animation sweatshop. they also do all the dialogue before any animation is doen. so they most likely just casted generic evil voices for everyone since they may have not know what deidara looked like at the time.