Mi Servirebbe Aiuto Per Spiegare Quest'errore

[kappuccio 5]

04:54 PM [sEVERE] java.lang.NoClassDefFoundError: net/minecraft/server/Block

04:54 PM [sEVERE] at com.sk89q.worldedit.bukkit.BukkitWorld.isValidBlockType(BukkitWorld.java:872)

04:54 PM [sEVERE] at com.sk89q.worldedit.WorldEdit.getBlock(WorldEdit.java:414)

04:54 PM [sEVERE] at com.sk89q.worldedit.WorldEdit.getBlock(WorldEdit.java:355)

04:54 PM [sEVERE] at com.sk89q.worldedit.WorldEdit.getBlock(WorldEdit.java:549)

04:54 PM [sEVERE] at com.sk89q.worldedit.WorldEdit.getBlockPattern(WorldEdit.java:625)

04:54 PM [sEVERE] at com.sk89q.worldedit.commands.RegionCommands.set(RegionCommands.java:74)

04:54 PM [sEVERE] at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)

04:54 PM [sEVERE] at sun.reflect.NativeMethodAccessorImpl.invoke(Unknown Source)

04:54 PM [sEVERE] at sun.reflect.DelegatingMethodAccessorImpl.invoke(Unknown Source)

04:54 PM [sEVERE] at java.lang.reflect.Method.invoke(Unknown Source)

04:54 PM [sEVERE] at com.sk89q.minecraft.util.commands.CommandsManager.invokeMethod(CommandsManager.java:522)

04:54 PM [sEVERE] at com.sk89q.worldedit.WorldEdit$1.invokeMethod(WorldEdit.java:241)

04:54 PM [sEVERE] at com.sk89q.worldedit.WorldEdit$1.invokeMethod(WorldEdit.java:172)

04:54 PM [sEVERE] at com.sk89q.minecraft.util.commands.CommandsManager.executeMethod(CommandsManager.java:509)

04:54 PM [sEVERE] at com.sk89q.minecraft.util.commands.CommandsManager.execute(CommandsManager.java:425)

04:54 PM [sEVERE] at com.sk89q.worldedit.WorldEdit.handleCommand(WorldEdit.java:1339)

04:54 PM [sEVERE] at com.sk89q.worldedit.bukkit.WorldEditPlugin.onCommand(WorldEditPlugin.java:197)

04:54 PM [sEVERE] at com.sk89q.bukkit.util.DynamicPluginCommand.execute(DynamicPluginCommand.java:52)

04:54 PM [sEVERE] at org.bukkit.command.SimpleCommandMap.dispatch(SimpleCommandMap.java:186)

04:54 PM [sEVERE] at org.bukkit.craftbukkit.v1_4_6.CraftServer.dispatchCommand(CraftServer.java:510)

04:54 PM [sEVERE] at net.minecraft.server.v1_4_6.PlayerConnection.handleCommand(PlayerConnection.java:980)

04:54 PM [sEVERE] at net.minecraft.server.v1_4_6.PlayerConnection.chat(PlayerConnection.java:898)

04:54 PM [sEVERE] at net.minecraft.server.v1_4_6.PlayerConnection.a(PlayerConnection.java:853)

04:54 PM [sEVERE] at net.minecraft.server.v1_4_6.Packet3Chat.handle(Packet3Chat.java:44)

04:54 PM [sEVERE] at net.minecraft.server.v1_4_6.NetworkManager.b(NetworkManager.java:290)

04:54 PM [sEVERE] at net.minecraft.server.v1_4_6.PlayerConnection.d(PlayerConnection.java:112)

04:54 PM [sEVERE] at net.minecraft.server.v1_4_6.ServerConnection.b(SourceFile:39)

04:54 PM [sEVERE] at net.minecraft.server.v1_4_6.DedicatedServerConnection.b(SourceFile:30)

04:54 PM [sEVERE] at net.minecraft.server.v1_4_6.MinecraftServer.r(MinecraftServer.java:598)

04:54 PM [sEVERE] at net.minecraft.server.v1_4_6.DedicatedServer.r(DedicatedServer.java:224)

04:54 PM [sEVERE] at net.minecraft.server.v1_4_6.MinecraftServer.q(MinecraftServer.java:494)

04:54 PM [sEVERE] at net.minecraft.server.v1_4_6.MinecraftServer.run(MinecraftServer.java:427)

04:54 PM [sEVERE] at net.minecraft.server.v1_4_6.ThreadServerApplication.run(SourceFile:849)

04:54 PM [sEVERE] Caused by: java.lang.ClassNotFoundException: net.minecraft.server.Block

04:54 PM [sEVERE] at org.bukkit.plugin.java.PluginClassLoader.findClass0(PluginClassLoader.java:70)

04:54 PM [sEVERE] at org.bukkit.plugin.java.PluginClassLoader.findClass(PluginClassLoader.java:53)

04:54 PM [sEVERE] at java.lang.ClassLoader.loadClass(Unknown Source)

04:54 PM [sEVERE] ... 33 more

Cosa significa? So solo che riguarda il mal funzionamento di worldedit nel mi server.