As the title states, I am completely lost on how to kill Josephina in the restore peace between the Elves and Dwarves quest.

I have tried using lightining (lvl 4), meteorstike (lvl 5), burning wall (lvl 5), summon skeleton (lvl 1), elemental strike (lvl 1), elemental hail (lvl 1), and various combinations of them. Of course, I also used both the anti-magic, and anti-physical attack sheilds as well as restoring all the time.

-Nothing works-

I am a mage, clearly, level 33. I have a huge supply of super magic potions so mana wasting is not an issue.
Whenever I go down there, she summons one of her Dread Knights on me, and that alone is hard since magic does nothing to them. -If- I killed one, I attempt to attack Josephina. She summons another one, and I am dead from a fury of hell spikes, and the hits of the Dread Knight.

Magic, apparently, also does not have an effect on her. She has a shield around her which stop me from using my powers on her. I cannot go melee, since I am a mage, and I have almost no expertiece (sp?) in the area of melee combat.

She is the first foe in the game who has halted me so much. My magery knew no bounds of destructiveness before.
What do I do? I have spent about 2 1/2 hours trying to get past this part...