Singelplayer Map machen World kopieren vom Saves Ordner und in deinen Server Ordner schieben!
oder gleich Bukkit
Da steht:
What you can control with settings file:
Biome sizes.
Temperature and moisture limits.
Caves generation.
World water level.
Terrain generation.
Tree density.
Ores generation.
Block replacement.
Custom object spawn.
Multi world support, config per world.
Viel Spass damit