I thought it might have been connected to the latency issues we have for the past days, but those issues are gone, yet the skills on my tank, and some other tanks friends of mine are not back to normal.
For some reason in all the instanes I've been entering, the boss monsters are unaffected by my "Provoke Aura", not to mention they resist all my agro skills.
What is more, the "Provoke Aura" itself seems to be working periodically, as if once in a while it was turning itself off completely, and turning back on after a while.
I know I am not an isolated case, since all the other tanks I know have this problem, but I just wonder if it is a bug that came into effect after all the recent lag related changes, or for some incomprehensible reason, this was done by design.