Skull of Pain not working correctly?

[ireaver]

Is the Skull of Pain broken? In Legend, I am pretty sure you received 50% rage at the start of a battle. I recently got the skull in KBAP and it's giving me no rage at all. It still takes half of my mana, though. Currently, it's at 50% strength, and I did not have one battle where it gave me rage at the start. I un-equipped / re-equipped, but still no rage. Anyone else see this? Is there another item that could be sapping rage at the beginning of a battle?

I'm playing Mage, btw.