Spawn skeleton in nether error

From what I know, this is by design. Regular skeletons can sometimes spawn in the nether as well as wither skeletons. In my opinion, this makes the nether much more challenging and fun.

Makes the Nether terrifying to be honest, the thought of walking along an edge surrounded by lava, only to be catapulted into it by a soaring arrow.
It's going to be a long time before I go back to the nether after 1.4, that's for certain.

That said, I don't think this is a bug, it'd be difficult to randomly cause a non-wither skeleton to spawn by accident.

Per the code it is intended to be this way. There is a 1 in 5 chance of a non wither skeleton spawning in the nether.

NeverCast, there are already blazes there to blast you into lava! There is no need for skeletons! they used to be an overworld mob!