2012-05-05 16:05:53 [INFO] null
2012-05-05 16:05:54 [SEVERE] java.util.ConcurrentModificationException
2012-05-05 16:05:54 [SEVERE] 	at java.util.ArrayList$Itr.checkForComodification(Unknown Source)
2012-05-05 16:05:54 [SEVERE] 	at java.util.ArrayList$Itr.next(Unknown Source)
2012-05-05 16:05:54 [SEVERE] 	at net.minecraft.server.World.tickEntities(World.java:1177)
2012-05-05 16:05:54 [SEVERE] 	at net.minecraft.server.MinecraftServer.w(MinecraftServer.java:542)
2012-05-05 16:05:54 [SEVERE] 	at net.minecraft.server.MinecraftServer.run(MinecraftServer.java:449)
2012-05-05 16:05:54 [SEVERE] 	at net.minecraft.server.ThreadServerApplication.run(SourceFile:492)
2012-05-05 16:05:54 [SEVERE] Unexpected exception
java.util.ConcurrentModificationException
	at java.util.ArrayList$Itr.checkForComodification(Unknown Source)
	at java.util.ArrayList$Itr.next(Unknown Source)
	at net.minecraft.server.World.tickEntities(World.java:1177)
	at net.minecraft.server.MinecraftServer.w(MinecraftServer.java:542)
	at net.minecraft.server.MinecraftServer.run(MinecraftServer.java:449)
	at net.minecraft.server.ThreadServerApplication.run(SourceFile:492)