error-from-log

2013-01-26 14:33:07 [SEVERE] java.lang.NoSuchMethodError: net.minecraft.server.v1_4_R1.Entity.getBukkitEntity()Lorg/bukkit/craftbukkit/v1_4_R1/entity/CraftEntity;
2013-01-26 14:33:07 [SEVERE]   at com.bergerkiller.bukkit.common.utils.NativeUtil.getEntity(NativeUtil.java:157)
2013-01-26 14:33:07 [SEVERE]   at com.bergerkiller.bukkit.common.internal.CommonWorldListener.a(CommonWorldListener.java:65)
2013-01-26 14:33:07 [SEVERE]   at net.minecraft.server.v1_4_R1.World.a(World.java:937)
2013-01-26 14:33:07 [SEVERE]   at net.minecraft.server.v1_4_R1.WorldServer.a(WorldServer.java:720)
2013-01-26 14:33:07 [SEVERE]   at net.minecraft.server.v1_4_R1.World.a(World.java:2405)
2013-01-26 14:33:07 [SEVERE]   at net.minecraft.server.v1_4_R1.Chunk.addEntities(Chunk.java:670)
2013-01-26 14:33:07 [SEVERE]   at net.minecraft.server.v1_4_R1.ChunkProviderServer.getChunkAt(ChunkProviderServer.java:128)
2013-01-26 14:33:07 [SEVERE]   at net.minecraft.server.v1_4_R1.ChunkProviderServer.getChunkAt(ChunkProviderServer.java:85)
2013-01-26 14:33:07 [SEVERE]   at net.minecraft.server.v1_4_R1.MinecraftServer.e(MinecraftServer.java:295)
2013-01-26 14:33:07 [SEVERE]   at net.minecraft.server.v1_4_R1.MinecraftServer.a(MinecraftServer.java:259)
2013-01-26 14:33:07 [SEVERE]   at net.minecraft.server.v1_4_R1.DedicatedServer.init(DedicatedServer.java:149)
2013-01-26 14:33:07 [SEVERE]   at net.minecraft.server.v1_4_R1.MinecraftServer.run(MinecraftServer.java:399)
2013-01-26 14:33:07 [SEVERE]   at net.minecraft.server.v1_4_R1.ThreadServerApplication.run(SourceFile:849)
2013-01-26 14:33:07 [SEVERE] Encountered an unexpected exception NoSuchMethodError
java.lang.NoSuchMethodError: net.minecraft.server.v1_4_R1.Entity.getBukkitEntity()Lorg/bukkit/craftbukkit/v1_4_R1/entity/CraftEntity;
 at com.bergerkiller.bukkit.common.utils.NativeUtil.getEntity(NativeUtil.java:157)
 at com.bergerkiller.bukkit.common.internal.CommonWorldListener.a(CommonWorldListener.java:65)
 at net.minecraft.server.v1_4_R1.World.a(World.java:937)
 at net.minecraft.server.v1_4_R1.WorldServer.a(WorldServer.java:720)
 at net.minecraft.server.v1_4_R1.World.a(World.java:2405)
 at net.minecraft.server.v1_4_R1.Chunk.addEntities(Chunk.java:670)
 at net.minecraft.server.v1_4_R1.ChunkProviderServer.getChunkAt(ChunkProviderServer.java:128)
 at net.minecraft.server.v1_4_R1.ChunkProviderServer.getChunkAt(ChunkProviderServer.java:85)
 at net.minecraft.server.v1_4_R1.MinecraftServer.e(MinecraftServer.java:295)
 at net.minecraft.server.v1_4_R1.MinecraftServer.a(MinecraftServer.java:259)
 at net.minecraft.server.v1_4_R1.DedicatedServer.init(DedicatedServer.java:149)
 at net.minecraft.server.v1_4_R1.MinecraftServer.run(MinecraftServer.java:399)
 at net.minecraft.server.v1_4_R1.ThreadServerApplication.run(SourceFile:849)
2013-01-26 14:33:07 [SEVERE] This crash report has been saved to: /home/minecraft/Minecraft/./crash-reports/crash-2013-01-26_14.33.07-server.txt