I spent about 6 hours in Kazham over the Memorial Day weekend levelling up great sword on these buggers (48drk/whm) and saw NO drops of chainmail. In fact, the only thing I saw was ONE goblin mask. I've also killed a bunch as drk/thf(15) and never saw any kind of armor.
Maybe they only drop mail in places like Ordelle's? Any ideas? I take great pleasure in killing them slowly.