Undead=Evil
I think the original poster made a valid point.
D&D doesn't do a good enough job of detailing _why_ the Undead state automatically makes a creature evil.
For example, why does becoming a lich automatically make one evil? And, why are the elven Baelnorns in FR exempt from this?
See the Vlad Taltos novels (Jhereg, etc) for a portrayal of undead (the lich Sethra Lavode?) that are not necessarily Evil.
I think there are some problems with the way Undeath is handled. For example, by the rules, raising your defeated enemy as a skeleton (for the price of a 50gp gem and a 3rd level spell), ordering it into a metal box, locking the box, and burying it functions as a poor man's Trap The Soul -- the equivalent of a 9th level spell!
Also, an earlier poster said that destroying an undead destroys the soul as well. I'd like to see a cite to the rules supporting this assertion -- I've never seen it.
To me, the rules should say the following:
a creature with the Undead subtype has Needs, which it craves and must seek, and these Needs always involve causing harm to living creatures. In general, the more powerful the Undead, the greater its control over its own Needs. "Mindless" undead, like skeletons and zombies, are completely overwhelmed by their Needs, are unable to think of anything else, and pursue them relentlessly unless commanded. "Intelligent" undead have needs but can think independently about other things. A Ghoul, for example, has the Need "Eat the flesh of sentient beings every day". A Vampire has the need "drink the blood of the living every day". A Vampire, which is much more powerful than a Ghoul, has an easier time (perhaps the WILL save mechanic could be used for this) temporarily suppressing its Need.
The "Needs" would thus be the basis for Undeath being Evil, since they drive the Undead creature to do Evil things, and the repeated execution of Evil acts is well known to corrupt the Soul.
Ken McKinney