Unliving Rage?

[master_marshmallow]

link

Quote:

This spell functions as rage, except it affects only undead creatures and bolsters them with necromantic energy rather than emotion. Each affected creature gains a +2 profane bonus to Strength and Constitution, a +1 profane bonus on Will saves, and a –2 penalty to AC. The effect is otherwise identical to a barbarian's rage.

Should this spell affect Charisma instead since undead have no Constitution?

[ericthecleric]

Yes.

Except that that spell isn't necessary.

An undead barbarian creature would gain Str/Cha boosts anyway.

From the PrD, for the undead type:
"•No Constitution score. Undead use their Charisma score in place of their Constitution score when calculating hit points, Fortitude saves, and any special ability that relies on Constitution (such as when calculating a breath weapon's DC)."
(bolded by me)

Also look at the vampire savage stat block in the PrD for the Monster Codex, under the vampire section.

[Berinor]

Got an unofficial yes from SKR back in August:

http://paizo.com/threads/rzs2rcio?Advanced-Class-Guide-Potential-Errors#19