Why are my biomes spawning like this in Minecraft?

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?

Why are my biomes spawning like this in Minecraft

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.