Bukkit/CraftBukkit — pull request #711 by steffengy (2012-03-07 14:16:02+00:00)
Title: Fixed nether-related-height-issues. The nether works now properly.

Fixes BUKKIT-976.
Fixed the code to spawn portals above the bedrock in nether (always)
The "useable not senseless" worldheight of nether is just 127.
Because to build above is anyway no sense.