Sanctuary + Amplify Damage/Decrepify

[Nimbostratus]

From what I've heard, the Sanctuary aura reduces the physical resistance of undead monsters to 0. However, if that monster was cursed by Amplify Damage or Decrepify, would its resistance go from a negative back up to 0, or would it remain negative?

[stfrn]

I belive it was "Sanctuary aura reduces the physical resistance of undead monsters to 0, unless it was already less then 0"