Entity Death

[SEVERE] Could not pass event ENTITY_DEATH to MobBounty
java.lang.NullPointerException
	at net.mcbat.MobBounty.Listeners.MobBountyEntityListener.onEntityDeath(MobBountyEntityListener.java:152)
	at org.bukkit.plugin.java.JavaPluginLoader$62.execute(JavaPluginLoader.java:677)
	at org.bukkit.plugin.RegisteredListener.callEvent(RegisteredListener.java:58)
	at org.bukkit.plugin.SimplePluginManager.callEvent(SimplePluginManager.java:339)
	at org.bukkit.craftbukkit.event.CraftEventFactory.callEntityDeathEvent(CraftEventFactory.java:285)
	at net.minecraft.server.EntityLiving.a(EntityLiving.java:545)
	at net.minecraft.server.EntityLiving.die(EntityLiving.java:528)
	at net.minecraft.server.EntityLiving.damageEntity(EntityLiving.java:469)
	at net.minecraft.server.EntityMonster.damageEntity(EntityMonster.java:44)
	at net.minecraft.server.EntityHuman.d(EntityHuman.java:720)
	at net.minecraft.server.NetServerHandler.a(NetServerHandler.java:915)
	at net.minecraft.server.Packet7UseEntity.a(SourceFile:33)
	at net.minecraft.server.NetworkManager.b(NetworkManager.java:226)
	at net.minecraft.server.NetServerHandler.a(NetServerHandler.java:92)
	at org.getspout.spout.SpoutNetServerHandler.a(SpoutNetServerHandler.java:500)
	at net.minecraft.server.NetworkListenThread.a(SourceFile:108)
	at net.minecraft.server.MinecraftServer.h(MinecraftServer.java:471)
	at net.minecraft.server.MinecraftServer.run(MinecraftServer.java:374)
	at net.minecraft.server.ThreadServerApplication.run(SourceFile:417)