2013-05-20 21:12:58 [SEVERE] Could not pass event EntityDamageByEntityEvent to mcMMO v1.4.05-b1870
org.bukkit.event.EventException
	at org.bukkit.plugin.java.JavaPluginLoader$1.execute(JavaPluginLoader.java:363)
	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.v1_4_R1.event.CraftEventFactory.callEvent(CraftEventFactory.java:63)
	at org.bukkit.craftbukkit.v1_4_R1.event.CraftEventFactory.callEntityDamageEvent(CraftEventFactory.java:351)
	at org.bukkit.craftbukkit.v1_4_R1.event.CraftEventFactory.handleEntityDamageEvent(CraftEventFactory.java:378)
	at md.a(EntityLiving.java:1117)
	at qj.a(EntityMob.java:73)
	at dan200.turtle.shared.TileEntityTurtle.tryPlaceOnEntity(TileEntityTurtle.java:1861)
	at dan200.turtle.shared.TileEntityTurtle.useStack(TileEntityTurtle.java:1952)
	at dan200.turtle.shared.TileEntityTurtle.attackWithItemStack(TileEntityTurtle.java:506)
	at dan200.turtle.shared.TurtleTool.attack(TurtleTool.java:131)
	at dan200.turtle.shared.TurtleTool.useTool(TurtleTool.java:116)
	at dan200.turtle.shared.TileEntityTurtle.useTool(TileEntityTurtle.java:1539)
	at dan200.turtle.shared.TileEntityTurtle.attack(TileEntityTurtle.java:1532)
	at dan200.turtle.shared.TileEntityTurtle.updateCommands(TileEntityTurtle.java:2552)
	at dan200.turtle.shared.TileEntityTurtle.g(TileEntityTurtle.java:2355)
	at yc.h(World.java:2597)
	at in.h(WorldServer.java:701)
	at net.minecraft.server.MinecraftServer.r(MinecraftServer.java:956)
	at ho.r(DedicatedServer.java:309)
	at net.minecraft.server.MinecraftServer.q(MinecraftServer.java:857)
	at net.minecraft.server.MinecraftServer.run(MinecraftServer.java:744)
	at fy.run(ThreadMinecraftServer.java:16)
Caused by: java.lang.NullPointerException
	at com.gmail.nossr50.util.skills.CombatUtils.combatChecks(Unknown Source)
	at com.gmail.nossr50.listeners.EntityListener.onEntityDamageByEntity(Unknown Source)
	at sun.reflect.GeneratedMethodAccessor52.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:361)
	... 24 more