NoLagg crash

12:30:59 [SEVERE] Could not pass event WorldLoadEvent to NoLagg
org.bukkit.event.EventException
        at org.bukkit.plugin.java.JavaPluginLoader$1.execute(JavaPluginLoader.java:332)
        at org.bukkit.plugin.RegisteredListener.callEvent(RegisteredListener.java:62)
        at org.bukkit.plugin.SimplePluginManager.fireEvent(SimplePluginManager.java:477)
        at org.bukkit.plugin.SimplePluginManager.callEvent(SimplePluginManager.java:462)
        at org.bukkit.craftbukkit.CraftServer.createWorld(CraftServer.java:730)
        at org.bukkit.Bukkit.createWorld(Bukkit.java:155)
        at multiworld.data.WorldManager.loadWorld(WorldManager.java:328)
        at multiworld.data.WorldManager.loadWorlds(WorldManager.java:602)
        at multiworld.data.DataHandler.loadWorlds(DataHandler.java:53)
        at multiworld.data.DataHandler.load(DataHandler.java:146)
        at multiworld.data.DataHandler.<init>(DataHandler.java:47)
        at multiworld.MultiWorldPlugin.onEnable(MultiWorldPlugin.java:81)
        at org.bukkit.plugin.java.JavaPlugin.setEnabled(JavaPlugin.java:217)
        at org.bukkit.plugin.java.JavaPluginLoader.enablePlugin(JavaPluginLoader.java:365)
        at org.bukkit.plugin.SimplePluginManager.enablePlugin(SimplePluginManager.java:381)
        at org.bukkit.craftbukkit.CraftServer.loadPlugin(CraftServer.java:265)
        at org.bukkit.craftbukkit.CraftServer.enablePlugins(CraftServer.java:247)
        at net.minecraft.server.MinecraftServer.i(MinecraftServer.java:296)
        at net.minecraft.server.MinecraftServer.d(MinecraftServer.java:275)
        at net.minecraft.server.MinecraftServer.a(MinecraftServer.java:225)
        at net.minecraft.server.DedicatedServer.init(DedicatedServer.java:140)
        at net.minecraft.server.MinecraftServer.run(MinecraftServer.java:378)
        at net.minecraft.server.ThreadServerApplication.run(SourceFile:539)
Caused by: java.lang.NoSuchFieldError: MAIN_THREAD
        at com.bergerkiller.bukkit.nolagg.threadcheck.ThreadCheck.check(ThreadCheck.java:62)
        at com.bergerkiller.bukkit.nolagg.threadcheck.Listener.onWorldLoad(Listener.java:96)
        at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
        at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:57)
        at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)
        at java.lang.reflect.Method.invoke(Method.java:601)
        at org.bukkit.plugin.java.JavaPluginLoader$1.execute(JavaPluginLoader.java:330)
        ... 22 more