Console Error Appearing Alot

this is appearing alot. i dont know why might be an issue with config file or sumthing
anyway running on mac osx lion intel i7 2600k 4 gb ram

ERROR:
13:09:14 [SEVERE] Could not pass event PlayerPickupItemEvent to NoLaggItemBuffer
org.bukkit.event.EventException
at org.bukkit.plugin.java.JavaPluginLoader$1.execute(JavaPluginLoader.java:303)
at org.bukkit.plugin.RegisteredListener.callEvent(RegisteredListener.java:62)
at org.bukkit.plugin.SimplePluginManager.callEvent(SimplePluginManager.java:459)
at net.minecraft.server.EntityArrow.a_(EntityArrow.java:352)
at net.minecraft.server.EntityHuman.l(EntityHuman.java:354)
at net.minecraft.server.EntityHuman.e(EntityHuman.java:346)
at net.minecraft.server.EntityLiving.F_(EntityLiving.java:447)
at net.minecraft.server.EntityHuman.F_(EntityHuman.java:159)
at net.minecraft.server.EntityPlayer.a(EntityPlayer.java:228)
at net.minecraft.server.NetServerHandler.a(NetServerHandler.java:341)
at net.minecraft.server.Packet10Flying.handle(SourceFile:126)
at net.minecraft.server.NetworkManager.b(NetworkManager.java:229)
at net.minecraft.server.NetServerHandler.a(NetServerHandler.java:113)
at net.minecraft.server.NetworkListenThread.a(NetworkListenThread.java:78)
at net.minecraft.server.MinecraftServer.w(MinecraftServer.java:551)
at net.minecraft.server.MinecraftServer.run(MinecraftServer.java:449)
at net.minecraft.server.ThreadServerApplication.run(SourceFile:492)
Caused by: java.lang.NullPointerException

 

ERROR:
13:09:14 [SEVERE] Could not pass event PlayerPickupItemEvent to NoLaggItemBuffer
org.bukkit.event.EventException

lately i seen many ppl have problems with nolagg try without it