I have searched bug reports and do not see anything on this issue, but I am fighting with Melee Merc's, they participate in the first 6 or 7 fights, then they just sit there for the next few fights? If I switch to another merc it makes no difference. If I stop fighting for 10 to 15 minutes and then resume they fight for a few fights again? Any ideas what might be causing this or what I might be able to do to fix?
Update: I switched to Tank merc's, fought 6 fights then they sat out on fight 7, 8 &9. Took a 5 minute break, pulled mob, no engagement. My group is a Warrior, Berserker, Shaman and a bard. After cool down I suspended Merc on Warrior and brought out Melee merc on Shaman, switched Berserker merc from Tank to Melee, pulled mob no engagements from the merc's
Well it seems I have solved my ISSUE, I am pulling with my tank and had the tank set as puller, was advised not to do that, fought 32 mobs the merc's engaged in all 32.