Severe Error

2012-09-30 12:59:35 [SEVERE] Could not pass event InventoryClickEvent to EmeraldEconLink
org.bukkit.event.EventException
	at org.bukkit.plugin.java.JavaPluginLoader$1.execute(JavaPluginLoader.java:304)
	at org.bukkit.plugin.RegisteredListener.callEvent(RegisteredListener.java:62)
	at org.bukkit.plugin.SimplePluginManager.fireEvent(SimplePluginManager.java:482)
	at org.bukkit.plugin.SimplePluginManager.callEvent(SimplePluginManager.java:467)
	at net.minecraft.server.NetServerHandler.a(NetServerHandler.java:1094)
	at net.minecraft.server.Packet102WindowClick.handle(SourceFile:28)
	at net.minecraft.server.NetworkManager.b(NetworkManager.java:234)
	at net.minecraft.server.NetServerHandler.a(NetServerHandler.java:119)
	at net.minecraft.server.NetworkListenThread.a(NetworkListenThread.java:83)
	at net.minecraft.server.MinecraftServer.w(MinecraftServer.java:579)
	at net.minecraft.server.MinecraftServer.run(MinecraftServer.java:467)
	at net.minecraft.server.ThreadServerApplication.run(SourceFile:492)
Caused by: java.lang.NoSuchFieldError: ENDER_CHEST
	at me.fonkfader.EmeraldEconLink.EmeraldEconLink.onClickEvent(EmeraldEconLink.java:1299)
	at sun.reflect.GeneratedMethodAccessor58.invoke(Unknown Source)
	at sun.reflect.DelegatingMethodAccessorImpl.invoke(Unknown Source)
	at java.lang.reflect.Method.invoke(Unknown Source)
	at org.bukkit.plugin.java.JavaPluginLoader$1.execute(JavaPluginLoader.java:302)
	... 11 more