Bukkit

What steps will reproduce the problem?
1. installing plugin

What is the expected output? What do you see instead?
plugin appears to work fine but I see this error message in server log.

What version of the product are you using?
using 1.3 on a 1.6.2 dev server so I just wanted to post this so a fix could make it into the next release.

Do you have an error log of what happened?
yes.
013-08-03 13:00:15 [SEVERE] Could not pass event EntityDamageByEntityEvent to YAPP v1.3
org.bukkit.event.EventException
    at org.bukkit.plugin.java.JavaPluginLoader$1.execute(JavaPluginLoader.java:427)
    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_6_R2.event.CraftEventFactory.callEvent(CraftEventFactory.java:95)
    at org.bukkit.craftbukkit.v1_6_R2.event.CraftEventFactory.callEntityDamageEvent(CraftEventFactory.java:383)
    at org.bukkit.craftbukkit.v1_6_R2.event.CraftEventFactory.handleEntityDamageEvent(CraftEventFactory.java:408)
    at net.minecraft.server.v1_6_R2.EntityLiving.damageEntity(EntityLiving.java:636)
    at net.minecraft.server.v1_6_R2.EntityHuman.damageEntity(EntityHuman.java:714)
    at net.minecraft.server.v1_6_R2.EntityPlayer.damageEntity(EntityPlayer.java:378)
    at net.minecraft.server.v1_6_R2.EntityMonster.m(EntityMonster.java:79)
    at net.minecraft.server.v1_6_R2.EntityMonster.a(EntityMonster.java:105)
    at net.minecraft.server.v1_6_R2.EntitySpider.a(EntitySpider.java:87)
    at net.minecraft.server.v1_6_R2.EntityCreature.bk(EntityCreature.java:66)
    at net.minecraft.server.v1_6_R2.EntityLiving.c(EntityLiving.java:1417)
    at net.minecraft.server.v1_6_R2.EntityInsentient.c(EntityInsentient.java:303)
    at net.minecraft.server.v1_6_R2.EntityMonster.c(EntityMonster.java:20)
    at net.minecraft.server.v1_6_R2.EntityLiving.l_(EntityLiving.java:1276)
    at net.minecraft.server.v1_6_R2.EntityInsentient.l_(EntityInsentient.java:147)
    at net.minecraft.server.v1_6_R2.EntityMonster.l_(EntityMonster.java:24)
    at net.minecraft.server.v1_6_R2.EntitySpider.l_(EntitySpider.java:18)
    at net.minecraft.server.v1_6_R2.World.entityJoinedWorld(World.java:1354)
    at net.minecraft.server.v1_6_R2.World.playerJoinedWorld(World.java:1335)
    at net.minecraft.server.v1_6_R2.World.tickEntities(World.java:1223)
    at net.minecraft.server.v1_6_R2.WorldServer.tickEntities(WorldServer.java:480)
    at net.minecraft.server.v1_6_R2.MinecraftServer.t(MinecraftServer.java:572)
    at net.minecraft.server.v1_6_R2.DedicatedServer.t(DedicatedServer.java:226)
    at net.minecraft.server.v1_6_R2.MinecraftServer.s(MinecraftServer.java:486)
    at net.minecraft.server.v1_6_R2.MinecraftServer.run(MinecraftServer.java:419)
    at net.minecraft.server.v1_6_R2.ThreadServerApplication.run(SourceFile:582)
Caused by: java.lang.NullPointerException
    at com.nisovin.yapp.denyperms.DamageListener.onDamage(DamageListener.java:55)
    at sun.reflect.GeneratedMethodAccessor4.invoke(Unknown Source)
    at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:25)
    at java.lang.reflect.Method.invoke(Method.java:597)
    at org.bukkit.plugin.java.JavaPluginLoader$1.execute(JavaPluginLoader.java:425)
    ... 29 more

The plugin is working fine for me, other than seeing this error message in the server log.