In Hexxat's quest, Ghostly Monks do not appear to be correctly identified as Undead. Turn Undead appears to do nothing to them, Daystar does not correctly deal double damage to them, False Dawn does not harm them, and so on. I do have SCS and Ascension installed, but to my knowledge neither should be altering the monks.
Expected Behaviour: Ghostly Monks should be undead, and affected by undead targetting spells and abilities accordingly, just like the Ghostly Priests (which are correctly functioning as Liches).
Edit: The same also appears to apply to the six lieutenants.