[Drachnon]

Sneak attack also works on undead and constructs in 4th adition I believe. The explination is that instead of going for vital points such as the heart or neck you hit their joints disabling them in some way.
Anyways I believe there was a way in 3.5 to get sneak attack on undead and constructs. Required some odd feat though.

[Tsunaru]

If there was, its not in the core books.

I never understood the logic behind undead getting immunity. Please explain it to me D XP.

Acrobatics feat of the week. Halfling jumping up a 15ft deep and 5ft wide pit by bouncing off alternating walls, requiring 7 successful throws (granted, my rank was higher than the first 3, so I only had to get 4 rolls. Thank god with the way I was rolling yesterday XD).

[Drachnon]

In 3.5 the reason that undead are immune to sneak attacks and critical hits is because both of these are discribed as a bit to a vital point of the target making them more dead then normal attacks. Since an undeads vitals don't work anyway they decided that they would be immune to such things. For the same reason poisons and mind affecting spells don't work because they lack the physiology that's usually affected by these.
Still nothing is more overpowered then constructs, a proper construct is immune to everything that might deliver instand kills, though it comes at the cost of harder to regain HP and no constitution (the last is more annouying then the first)

[DDv]

There are prestige classes with feats that make you able to land critical hits on undeads or constructs. I don't like them.

Tsunaru: It's just like Drachnon said. An undead can go without a head. It doesn't need anything to live, since it's not alive. Btw, I wish I'd roll like that all the time. :)

[Tsunaru]

Alright, sneak attack makes sense then. But criticals dont. If you can do damage to something, logic dictates extra damage should also be possible. You dont get a crit by hitting their weak points or anything, its with pure, crushing power =p

[DDv]

Sneak attack and critical hits work the same way. The only diffrence is that sneak attack is intentional.

[Tsunaru]

Not exactly. Sneak attack is more of precision based attack, where you pick a certain vital area to strike for extra damage. A critical is an attack with more oomph, some extra crushing momentum if you will. Undead are immune to sneak attacks due to the lack of vitals, but critical doesnt attack vitals, its just a heavier hit. The only things I can see criticals acting as a vital attack would be in the case of weapons usable with Weapon Finesse.

Either way, the injustice was fixed in 4.0 and Pathfinder, so it doesnt really matter XP. Though leaving them immune to sneak attack would have made sense. It was really just the critical thing that confused/pissed me off =p

[DDv]

I still paly 3.5 so that doesn't really satisfy me. :P

[Tsunaru]

Dude, you should switch over to Pathfinder. Its so much better than 3.5 XD

[DDv]

It's up to the group, not just me.