I have a legal copy of minecraft that I purchased. Recently every time I create a server from my home computer, all the biomes spawn like this (picture in link below). I was running a bukkit server at one point but I deleted all of the files and mods (I think). Is there any way maybe in the registry that I missed some bukkit files? Has anyone else been experiencing this? Is there any way to fix this?
That happens quite often whether you're using mods/plugins or just vanilla. It is because the biomes are too close. Only way to sort it is to either keep regenerating a new world or use a seed for a world that looks good.
It's just a chunk error try to reload or uninstall mods
This happened to a lot of worlds when servers updated to 1.7. The old generation clashed with the new terrain and caused these cliff like generations.