Once you attack a combat dummy the dummy tries to attack you back. So, even if you attacked the dummy a long time ago and you left the area and came back as soon as you stand near enough to the dummy it will take a swing at you (and you will automatically enter combat and counter attack).

Small bug, but having actions in objects' action queques that can not completed seems like a bad idea.

(tested with a dummy in the Tigereye fortress)

One point, if they get an AOO on you for whatever reason, they come "alive". Its an engine thing. The crone is it, those ones work fine so it may just be that specific set in the fortress.

I think that this has been fixed. I couldn't duplicate the issue.