20:45:57 [SEVERE] java.lang.NoSuchMethodError: net.minecraft.server.ItemInWorldM
anager.a(I)V
20:45:57 [SEVERE]       at net.citizensnpcs.resources.npclib.CraftNPC.<init>(Cra
ftNPC.java:17)
20:45:57 [SEVERE]       at net.citizensnpcs.resources.npclib.NPCSpawner.spawnNPC
(NPCSpawner.java:75)
20:45:57 [SEVERE]       at net.citizensnpcs.resources.npclib.NPCManager.register
(NPCManager.java:159)
20:45:57 [SEVERE]       at net.citizensnpcs.resources.npclib.NPCManager.register
(NPCManager.java:189)
20:45:57 [SEVERE]       at net.citizensnpcs.commands.BasicCommands.create(BasicC
ommands.java:226)
20:45:57 [SEVERE]       at sun.reflect.NativeMethodAccessorImpl.invoke0(Native M
ethod)
20:45:57 [SEVERE]       at sun.reflect.NativeMethodAccessorImpl.invoke(Unknown S
ource)
20:45:57 [SEVERE]       at sun.reflect.DelegatingMethodAccessorImpl.invoke(Unkno
wn Source)
20:45:57 [SEVERE]       at java.lang.reflect.Method.invoke(Unknown Source)
20:45:57 [SEVERE]       at net.citizensnpcs.resources.sk89q.CommandsManager.exec
uteMethod(CommandsManager.java:530)
20:45:57 [SEVERE]       at net.citizensnpcs.resources.sk89q.CommandsManager.exec
ute(CommandsManager.java:407)
20:45:57 [SEVERE]       at net.citizensnpcs.Citizens.onCommand(Citizens.java:200
)
20:45:57 [SEVERE]       at org.bukkit.command.PluginCommand.execute(PluginComman
d.java:40)
20:45:57 [SEVERE]       at org.bukkit.command.SimpleCommandMap.dispatch(SimpleCo
mmandMap.java:168)
20:45:57 [SEVERE]       at org.bukkit.craftbukkit.CraftServer.dispatchCommand(Cr
aftServer.java:382)
20:45:57 [SEVERE]       at net.minecraft.server.NetServerHandler.handleCommand(N
etServerHandler.java:768)
20:45:57 [SEVERE]       at net.minecraft.server.NetServerHandler.chat(NetServerH
andler.java:728)
20:45:57 [SEVERE]       at net.minecraft.server.NetServerHandler.a(NetServerHand
ler.java:721)
20:45:57 [SEVERE]       at net.minecraft.server.Packet3Chat.a(Packet3Chat.java:3
3)
20:45:57 [SEVERE]       at net.minecraft.server.NetworkManager.b(NetworkManager.
java:226)
20:45:57 [SEVERE]       at net.minecraft.server.NetServerHandler.a(NetServerHand
ler.java:96)
20:45:57 [SEVERE]       at net.minecraft.server.NetworkListenThread.a(SourceFile
:108)
20:45:57 [SEVERE]       at net.minecraft.server.MinecraftServer.w(MinecraftServe
r.java:534)
20:45:57 [SEVERE]       at net.minecraft.server.MinecraftServer.run(MinecraftSer
ver.java:432)
20:45:57 [SEVERE]       at net.minecraft.server.ThreadServerApplication.run(Sour
ceFile:465)