1. 21:34:53 [SEVERE] Exception in thread "Thread-6"
  2. 21:34:53 [SEVERE] java.util.ConcurrentModificationException
  3. 21:34:53 [SEVERE] at java.util.AbstractList$Itr.checkForComodification(AbstractList.java:372)
  4. 21:34:53 [SEVERE] at java.util.AbstractList$Itr.next(AbstractList.java:343)
  5. 21:34:53 [SEVERE] at org.bukkit.craftbukkit.CraftWorld.getLivingEntities(CraftWorld.java:520)
  6. 21:34:53 [SEVERE] at me.xXLupoXx.NoSpawn.MobCounter.run(MobCounter.java:71)