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2012-02-10 16:47:09 [SEVERE] Could not pass event org.bukkit.event.block.BlockPhysicsEvent to V10lift
org.bukkit.event.EventException
	at org.bukkit.plugin.java.JavaPluginLoader$103.execute(JavaPluginLoader.java:1026)
	at org.bukkit.plugin.RegisteredListener.callEvent(RegisteredListener.java:57)
	at org.bukkit.plugin.SimplePluginManager.callEvent(SimplePluginManager.java:453)
	at net.minecraft.server.World.k(World.java:518)
	at net.minecraft.server.World.applyPhysics(World.java:503)
	at net.minecraft.server.World.update(World.java:467)
	at net.minecraft.server.World.setTypeId(World.java:439)
	at net.minecraft.server.EntitySheep.m_(EntitySheep.java:90)
	at net.minecraft.server.EntityLiving.d(EntityLiving.java:945)
	at net.minecraft.server.EntityAnimal.d(EntityAnimal.java:29)
	at net.minecraft.server.EntitySheep.d(EntitySheep.java:48)
	at net.minecraft.server.EntityLiving.y_(EntityLiving.java:339)
	at net.minecraft.server.World.entityJoinedWorld(World.java:1258)
	at net.minecraft.server.WorldServer.entityJoinedWorld(WorldServer.java:110)
	at net.minecraft.server.World.playerJoinedWorld(World.java:1240)
	at net.minecraft.server.World.tickEntities(World.java:1147)
	at net.minecraft.server.MinecraftServer.w(MinecraftServer.java:528)
	at net.minecraft.server.MinecraftServer.run(MinecraftServer.java:435)
	at net.minecraft.server.ThreadServerApplication.run(SourceFile:465)
Caused by: java.lang.reflect.InvocationTargetException
	at sun.reflect.GeneratedMethodAccessor1.invoke(Unknown Source)
	at sun.reflect.DelegatingMethodAccessorImpl.invoke(Unknown Source)
	at java.lang.reflect.Method.invoke(Unknown Source)
	at org.bukkit.plugin.java.JavaPluginLoader$103.execute(JavaPluginLoader.java:1024)
	... 18 more
Caused by: java.lang.NullPointerException