Good undead camps for a 25 pally?

[Velerin]

There's a handful of "a skeleton" in Najena that are level ~23ish. Great exp in that zone. Once you learn the spots you can do a rotation of about 4 plus the tent terrors. Even some of used to be light blues/now green give pretty decent exp around that level. Only downside is there are lots of annoying green trash you'll have to agro near the entrance as a paly.

[Tuljin]

Around level 30 you'll want to take the Sword of Morning over the Ghoulbane because the procs from GB become way less devastating and you'll want the extra dps from the Sword. Unrest is really your best bet for XP and you'll have to go at times when its not crowded. When you get Stun at level 30 you'll be able to solo Festering Hags by using Stun and Bash to knock out their spells. This is dangerous and requires skill but they have low HP, when you fight melee mobs it will take a while to beat them down cause of high HP and low pal DPS and you'll drain your mana bar healing. You should find a Rogue to duo with - pal/rog is a great duo, esp when you get stun and you can wreck caster mobs.