Bukkit

• Support for CraftBukkit 1.3.1-R1.0
• Support for the new Minecraft materials, try EMERALD_ORE and the like.
• Supports custom data values (add a dash and the value, see below)
• Supports integer material IDs
• Unique systems for each world, when using a multi world plugin.

New material examples (in config.yml):

Blue Wool: - WOOL-1.0-11 or - 35-1.0-11 If you have a mod that adds a new material with an ID of 140: - 140-1.0 If you have a mod that adds a new material with ID 140 and sub-ID of 3: - 140-1.0-3

NOT BACKWARDS COMPATIBLE WITH OLDER PLANETOIDS VERSIONS!  Try it with a new world or risk messing up your old one.  Worlds from the recent Beta v1.4.0 should work though.

Last time I checked, Bukkit still imposes a maximum height limit of 256.