WP

http://www.uoguide.com/Wraith_Form

This is what I have always understood of wraith form. While in Wraith and say you cast Wither in a mob, you should get some mana drain/leech. Quoting from the link above at 100 Spirit Speak I would get 20% of the damage dealt to mob. So if I hit a mob for 50 I would get 10 mana back from it. In a champ mob this would basically always keep your mana maxed out(due to the number of mobs) and you should never run out of mana, as long as you are hitting something.

If I am wrong about this please point me in the correct direction.
If I am right please confirm this.

I have tested this and receive no mana drain/leech affects.

N'ruz

Make sure the creatures you are trying to leech from have mana. If they have no mana you get none in return. Try using it on an evil mage and see what happens. I swear I remember seeing this come up on the live server when I played. Ill try and find it.