PVP plus error??? help

Got this error everytime a monster attack me



[22:11:23 [SEVERE] Could not pass event ENTITY_DAMAGE to PvPplus
java.lang.ClassCastException: org.bukkit.craftbukkit.entity.CraftSkeleton cannot
be cast to org.bukkit.entity.Player
at randy.pvpp.pvppEntityListener.onEntityDamage(pvppEntityListener.java:
19)
at org.bukkit.plugin.java.JavaPluginLoader$63.execute(JavaPluginLoader.j
ava:684)
at org.bukkit.plugin.RegisteredListener.callEvent(RegisteredListener.jav
a:58)
at org.bukkit.plugin.SimplePluginManager.callEvent(SimplePluginManager.j
ava:339)
at net.minecraft.server.EntityArrow.s_(EntityArrow.java:192)
at net.minecraft.server.World.entityJoinedWorld(World.java:1193)
at net.minecraft.server.WorldServer.entityJoinedWorld(WorldServer.java:1
04)
at net.minecraft.server.World.playerJoinedWorld(World.java:1175)
at net.minecraft.server.World.tickEntities(World.java:1090)
at net.minecraft.server.MinecraftServer.h(MinecraftServer.java:467)
at net.minecraft.server.MinecraftServer.run(MinecraftServer.java:374)
at net.minecraft.server.ThreadServerApplication.run(SourceFile:417)]

 

Ask the author of the plugin what's wrong, seems like an error in the code.