Can confirm this awesome bug report
[You must be logged in to view images. Log in or Register.] , after the server reset earlier today ( at least so it seemed), all my slows did nothing to targets attack speed. No messages about resists, does not take hold or any of that sort. But could definately tell they weren't slowed. Tried just about all from the Shaman line, enchanter friend tried Shiftless Deeds and the same result. All this was in Nagafen's Lair. Didn't test on a whole lot of mob's, but at least Imps and the beetles.
5 hours later in the Hole and all slows landed perfect.
Very little testing, sorry about that. But limited play time