lwc error

2011-04-06 12:30:36 [SEVERE] Could not pass event PLAYER_INTERACT to LWC
java.lang.LinkageError: com/nijiko/permissions/PermissionHandler
	at com.griefcraft.listeners.LWCPlayerListener.onPlayerInteract(LWCPlayerListener.java:138)
	at org.bukkit.plugin.java.JavaPluginLoader$9.execute(JavaPluginLoader.java:217)
	at org.bukkit.plugin.RegisteredListener.callEvent(RegisteredListener.java:59)
	at org.bukkit.plugin.SimplePluginManager.callEvent(SimplePluginManager.java:255)
	at org.bukkit.craftbukkit.event.CraftEventFactory.callPlayerInteractEvent(CraftEventFactory.java:162)
	at net.minecraft.server.ItemInWorldManager.a(ItemInWorldManager.java:207)
	at net.minecraft.server.NetServerHandler.a(NetServerHandler.java:447)
	at net.minecraft.server.Packet15Place.a(SourceFile:57)
	at net.minecraft.server.NetworkManager.a(NetworkManager.java:198)
	at net.minecraft.server.NetServerHandler.a(NetServerHandler.java:72)
	at net.minecraft.server.NetworkListenThread.a(SourceFile:100)
	at net.minecraft.server.MinecraftServer.h(MinecraftServer.java:368)
	at net.minecraft.server.MinecraftServer.run(MinecraftServer.java:283)
	at net.minecraft.server.ThreadServerApplication.run(SourceFile:375