Fehler bei ChestShop

2012-07-27 15:49:54 [SEVERE] Could not pass event SignChangeEvent to ChestShop
org.bukkit.event.EventException
	at org.bukkit.plugin.java.JavaPluginLoader$1.execute(JavaPluginLoader.java:304)
	at org.bukkit.plugin.RegisteredListener.callEvent(RegisteredListener.java:62)
	at org.bukkit.plugin.SimplePluginManager.callEvent(SimplePluginManager.java:460)
	at net.minecraft.server.NetServerHandler.a(NetServerHandler.java:1266)
	at net.minecraft.serverhook.NetServerHandlerProxy.a(NetServerHandlerProxy.java:217)
	at net.minecraft.server.Packet130UpdateSign.handle(SourceFile:41)
	at net.minecraft.server.NetworkManager.b(NetworkManager.java:229)
	at net.minecraft.server.NetServerHandler.a(NetServerHandler.java:113)
	at net.minecraft.serverhook.NetServerHandlerProxy.a(NetServerHandlerProxy.java:83)
	at net.minecraft.server.NetworkListenThread.a(NetworkListenThread.java:78)
	at net.minecraft.server.MinecraftServer.w(MinecraftServer.java:567)
	at net.minecraft.server.MinecraftServer.run(MinecraftServer.java:459)
	at net.minecraft.server.ThreadServerApplication.run(SourceFile:492)
Caused by: java.lang.NumberFormatException: For input string: ""
	at java.lang.NumberFormatException.forInputString(NumberFormatException.java:65)
	at java.lang.Long.parseLong(Long.java:453)
	at com.Acrobot.Breeze.Utils.MaterialUtil$Enchantment.getEnchantments(MaterialUtil.java:246)
	at com.Acrobot.Breeze.Utils.MaterialUtil.getEnchantments(MaterialUtil.java:229)
	at com.Acrobot.Breeze.Utils.MaterialUtil.getItem(MaterialUtil.java:182)
	at com.Acrobot.ChestShop.Listeners.Block.SignChange.onSignChange(SignChange.java:43)
	at sun.reflect.GeneratedMethodAccessor383.invoke(Unknown Source)
	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:302)
	... 12 more