2012-10-14 10:04:55 [WARNING] CraftBook mechanic: Failed to think for com.sk89q.craftbook.ic.SelfTriggeredICMechanic
java.util.ConcurrentModificationException
	at java.util.ArrayList$Itr.checkForComodification(ArrayList.java:819)
	at java.util.ArrayList$Itr.next(ArrayList.java:791)
	at org.bukkit.craftbukkit.CraftWorld.getPlayers(CraftWorld.java:682)
	at com.sk89q.craftbook.gates.world.PotionInducer.think(PotionInducer.java:55)
	at com.sk89q.craftbook.ic.SelfTriggeredICMechanic.think(SelfTriggeredICMechanic.java:51)
	at com.sk89q.craftbook.MechanicManager.think(MechanicManager.java:628)
	at com.sk89q.craftbook.bukkit.MechanicClock.run(MechanicClock.java:35)
	at org.bukkit.craftbukkit.scheduler.CraftTask.run(CraftTask.java:52)
	at org.bukkit.craftbukkit.scheduler.CraftScheduler.mainThreadHeartbeat(CraftScheduler.java:321)
	at net.minecraft.server.MinecraftServer.q(MinecraftServer.java:510)
	at net.minecraft.server.DedicatedServer.q(DedicatedServer.java:213)
	at net.minecraft.server.MinecraftServer.p(MinecraftServer.java:474)
	at net.minecraft.server.MinecraftServer.run(MinecraftServer.java:405)
	at net.minecraft.server.ThreadServerApplication.run(SourceFile:539)