Just curious if they implemented that particular rule.

Also, do any enemies use turn undead against you?

I always have a Paladin in my party (no GB games that cater for evil parties anyway), and I've never seen it happen.
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No, and there are only two sides to a battle and n̶o̶ ̶p̶l̶a̶y̶e̶r̶-̶c̶o̶n̶t̶r̶o̶l̶l̶e̶d̶ ̶u̶n̶d̶e̶a̶d̶ disregard that, PoR has some, so n̶o̶ ̶a̶g̶a̶i̶n̶ probably still not.

In PoR you can use Animate Dead on your own team members and have undead on your team. I remember using that at least once, at a point where I didn't have enough money to raise a dead party member.

O.o and I always thought it was an engine restriction, along with other unimplemented neat / iconic / obvious stuff (equipment queries for one). There should have been way more awesome original O.o-inducing things done with an engine which allows for PC undeath.