OK, this is going to sound crazy, but if a Paladin can hit a person with a touch attack, they can use Lay on Hands on them from any range, as long as they are on the same plane.
Why? There's a 4th level spell called Sacred Haven in the BoED that, among other things, removes any sort of range restriction from your Lay on Hands.
If you have levels in Grayguard, you can deal damage with your Lay on Hands.
Now, since you have to be close enough to hit them with a touch attack (or just use Reach spell with it, but that don't work as well), it is kinda less useful, but...
The spell also gives you a Status effect on the person it is affecting. And, well, get a Familiar and then...
Profit.
After all, who's gonna have a problem with an adorable kitty rubbing up against them (OK, maybe when all the blood in their bodies leave via their ears...)
So, yeah, hit the spell with DMM: Persist, and you can kill them at your leisure over the course of the day.