Once I killed Firkraag in about 30 seconds:
First I cast a lower resistance on him before he spoke (slight cheese, with old version [img]tongue.gif[/img] )
Then I sent my fighter types, (Me, Minsc, Jaheira) to keep him busy so he wouldn't attack my magic users.
Next I think (can't quite remember) I cast a greater malison, followed by a Finger of Death, which worked!