Are you an enchanter by chance? My chanter got it as well, but only after using my T2 robe clicky. Maybe Cerebral Breach has something to do with it?
Edit: I was right
Cerebral Breach
1: Add Effect: Form of Mana
7: Increase Mana by 720 per tick
I'm guessing it has 28h because of permanent illusion. YAY new illusion
Edited, Aug 24th 2011 4:28pm by baketomato