Its neat how we can stun undead with PS at will. I was thinking we could add the ability to cast on a weapon, giving the weapon the ability to stun undead similarly to how bless enables us to hit undead/hit undead better for X number of strikes.

The chance to stun would scale to the ability of the caster, up to (and perhaps more often at higher skill) the chance to stun for normal critters.

Ah yes, and I like your suggestion too.