Exception in server tick loop

---- Minecraft Crash Report ----
// I bet Cylons wouldn't have this problem.

Time: 05/05/13 10:27
Description: Exception in server tick loop

java.util.ConcurrentModificationException
	at java.util.LinkedList$ListItr.checkForComodification(Unknown Source)
	at java.util.LinkedList$ListItr.next(Unknown Source)
	at codechicken.chunkloader.PlayerChunkViewerManager.update(PlayerChunkViewerManager.java:104)
	at codechicken.chunkloader.ChunkLoaderEventHandler.tickEnd(ChunkLoaderEventHandler.java:35)
	at cpw.mods.fml.common.SingleIntervalHandler.tickEnd(SingleIntervalHandler.java:22)
	at cpw.mods.fml.common.FMLCommonHandler.tickEnd(FMLCommonHandler.java:139)
	at cpw.mods.fml.common.FMLCommonHandler.onPostServerTick(FMLCommonHandler.java:275)
	at net.minecraft.server.MinecraftServer.q(MinecraftServer.java:634)
	at bdz.q(IntegratedServer.java:123)
	at net.minecraft.server.MinecraftServer.run(MinecraftServer.java:497)
	at fy.run(SourceFile:849)


A detailed walkthrough of the error, its code path and all known details is as follows:
---------------------------------------------------------------------------------------

-- System Details --
Details:
	Minecraft Version: 1.4.7
	Operating System: Windows 7 (amd64) version 6.1
	Java Version: 1.7.0_21, Oracle Corporation
	Java VM Version: Java HotSpot(TM) 64-Bit Server VM (mixed mode), Oracle Corporation
	Memory: 170169880 bytes (162 MB) / 628039680 bytes (598 MB) up to 2381053952 bytes (2270 MB)
	JVM Flags: 8 total; -Xms256M -Xmx2304M -XX:+UseConcMarkSweepGC -XX:+CMSIncrementalMode -XX:+AggressiveOpts -XX:+CMSClassUnloadingEnabled -XX:MaxPermSize=128m -XX:PermSize=128m
	AABB Pool Size: 2740 (153440 bytes; 0 MB) allocated, 2717 (152152 bytes; 0 MB) used
	Suspicious classes: FML and Forge are installed
	IntCache: cache: 0, tcache: 0, allocated: 3, tallocated: 63
	FML: MCP v7.26a FML v4.7.35.556 Minecraft Forge 6.6.2.534 Feed The Beast Mod Pack 67 mods loaded, 67 mods active
	mcp [Minecraft Coder Pack] (minecraft.jar) Unloaded->Constructed->Pre-initialized->Initialized->Post-initialized->Available->Available->Available->Available
	FML [Forge Mod Loader] (coremods) Unloaded->Constructed->Pre-initialized->Initialized->Post-initialized->Available->Available->Available->Available
	Forge [Minecraft Forge] (coremods) Unloaded->Constructed->Pre-initialized->Initialized->Post-initialized->Available->Available->Available->Available
	CodeChickenCore [CodeChicken Core] (coremods) Unloaded->Constructed->Pre-initialized->Initialized->Post-initialized->Available->Available->Available->Available
	MiscPeripheralsASM [MiscPeripherals ASM] (coremods) Unloaded->Constructed->Pre-initialized->Initialized->Post-initialized->Available->Available->Available->Available
	NotEnoughItems [Not Enough Items] (coremods) Unloaded->Constructed->Pre-initialized->Initialized->Post-initialized->Available->Available->Available->Available
	ComputerCraft [ComputerCraft] (computercraft.zip) Unloaded->Constructed->Pre-initialized->Initialized->Post-initialized->Available->Available->Available->Available
	CCTurtle [ComputerCraft Turtles] (computercraft.zip) Unloaded->Constructed->Pre-initialized->Initialized->Post-initialized->Available->Available->Available->Available
	MiscPeripherals [MiscPeripherals] (MiscPeripherals.jar) Unloaded->Constructed->Pre-initialized->Initialized->Post-initialized->Available->Available->Available->Available
	AppliedEnergistics [Applied Energistics] (AppliedEnergistics.zip) Unloaded->Constructed->Pre-initialized->Initialized->Post-initialized->Available->Available->Available->Available
	BuildCraft|Core [BuildCraft] (buildcraft.jar) Unloaded->Constructed->Pre-initialized->Initialized->Post-initialized->Available->Available->Available->Available
	BuildCraft|Builders [BC Builders] (buildcraft.jar) Unloaded->Constructed->Pre-initialized->Initialized->Post-initialized->Available->Available->Available->Available
	BuildCraft|Energy [BC Energy] (buildcraft.jar) Unloaded->Constructed->Pre-initialized->Initialized->Post-initialized->Available->Available->Available->Available
	BuildCraft|Factory [BC Factory] (buildcraft.jar) Unloaded->Constructed->Pre-initialized->Initialized->Post-initialized->Available->Available->Available->Available
	BuildCraft|Transport [BC Transport] (buildcraft.jar) Unloaded->Constructed->Pre-initialized->Initialized->Post-initialized->Available->Available->Available->Available
	BuildCraft|Silicon [BC Silicon] (buildcraft.jar) Unloaded->Constructed->Pre-initialized->Initialized->Post-initialized->Available->Available->Available->Available
	CoFHCore [CoFH Core] (CoFHCore.zip) Unloaded->Constructed->Pre-initialized->Initialized->Post-initialized->Available->Available->Available->Available
	ThermalExpansion [Thermal Expansion] (thermalexpansion.zip) Unloaded->Constructed->Pre-initialized->Initialized->Post-initialized->Available->Available->Available->Available
	OmniTools [OmniTools] (omnitools.zip) Unloaded->Constructed->Pre-initialized->Initialized->Post-initialized->Available->Available->Available->Available
	IC2 [IndustrialCraft 2] (IC2.jar) Unloaded->Constructed->Pre-initialized->Initialized->Post-initialized->Available->Available->Available->Available
	ChargePads [Charge Pads] (ChargePads.zip) Unloaded->Constructed->Pre-initialized->Initialized->Post-initialized->Available->Available->Available->Available
	ChickenChunks [ChickenChunks] (ChickenChunks.jar) Unloaded->Constructed->Pre-initialized->Initialized->Post-initialized->Available->Available->Available->Available
	CompactSolars [Compact Solar Arrays] (compactsolars.zip) Unloaded->Constructed->Pre-initialized->Initialized->Post-initialized->Available->Available->Available->Available
	EE3 [Equivalent Exchange 3] (ee3.jar) Unloaded->Constructed->Pre-initialized->Initialized->Post-initialized->Available->Available->Available->Available
	EnderStorage [EnderStorage] (EnderStorage.jar) Unloaded->Constructed->Pre-initialized->Initialized->Post-initialized->Available->Available->Available->Available
	ExtrabiomesXL [ExtrabiomesXL] (extrabiomes.jar) Unloaded->Constructed->Pre-initialized->Initialized->Post-initialized->Available->Available->Available->Available
	Forestry [Forestry for Minecraft] (forestry.jar) Unloaded->Constructed->Pre-initialized->Initialized->Post-initialized->Available->Available->Available->Available
	BinnieCore [Binnie Core] (extrabees.zip) Unloaded->Constructed->Pre-initialized->Initialized->Post-initialized->Available->Available->Available->Available
	ExtraBees [Extra Bees] (extrabees.zip) Unloaded->Constructed->Pre-initialized->Initialized->Post-initialized->Available->Available->Available->Available
	factorization [Factorization] (factorization.jar) Unloaded->Constructed->Pre-initialized->Initialized->Post-initialized->Available->Available->Available->Available
	GraviGun [GraviGun] (GraviGun.zip) Unloaded->Constructed->Pre-initialized->Initialized->Post-initialized->Available->Available->Available->Available
	GraviSuite [Gravitation Suite] (gravisuite.zip) Unloaded->Constructed->Pre-initialized->Initialized->Post-initialized->Available->Available->Available->Available
	IC2NuclearControl [Nuclear Control] (IC2NuclearControl.zip) Unloaded->Constructed->Pre-initialized->Initialized->Post-initialized->Available->Available->Available->Available
	mod_InvTweaks [Inventory Tweaks] (InvTweaks.zip) Unloaded->Constructed->Pre-initialized->Initialized->Post-initialized->Available->Available->Available->Available
	IronChest [Iron Chest] (IronChest.zip) Unloaded->Constructed->Pre-initialized->Initialized->Post-initialized->Available->Available->Available->Available
	ModularForceFieldSystem [Modular ForceField System V2] (modularforcefieldsystem.zip) Unloaded->Constructed->Pre-initialized->Initialized->Post-initialized->Available->Available->Available->Available
	mmmPowersuits [MachineMuse's Modular Powersuits] (ModularPowersuits.jar) Unloaded->Constructed->Pre-initialized->Initialized->Post-initialized->Available->Available->Available->Available
	Mystcraft [Mystcraft] (mystcraft.zip) Unloaded->Constructed->Pre-initialized->Initialized->Post-initialized->Available->Available->Available->Available
	NEIPlugins [NEI Plugins] (neiplugins.jar) Unloaded->Constructed->Pre-initialized->Initialized->Post-initialized->Available->Available->Available->Available
	ObsidiPlates [Obsidian Pressure Plates] (obsidiplates.zip) Unloaded->Constructed->Pre-initialized->Initialized->Post-initialized->Available->Available->Available->Available
	PortalGun [Portal Gun] (PortalGun.zip) Unloaded->Constructed->Pre-initialized->Initialized->Post-initialized->Available->Available->Available->Available
	Railcraft [Railcraft] (railcraft.jar) Unloaded->Constructed->Pre-initialized->Initialized->Post-initialized->Available->Available->Available->Available
	RedPowerCore [RedPower] (redpowercore.zip) Unloaded->Constructed->Pre-initialized->Initialized->Post-initialized->Available->Available->Available->Available
	RedPowerBase [RP Base] (redpowercore.zip) Unloaded->Constructed->Pre-initialized->Initialized->Post-initialized->Available->Available->Available->Available
	RedPowerMachine [RP Machine] (redpowermechanical.zip) Unloaded->Constructed->Pre-initialized->Initialized->Post-initialized->Available->Available->Available->Available
	RedPowerCompat [RP Compat] (redpowercompat.zip) Unloaded->Constructed->Pre-initialized->Initialized->Post-initialized->Available->Available->Available->Available
	RedPowerWiring [RP Wiring] (redpowerdigital.zip) Unloaded->Constructed->Pre-initialized->Initialized->Post-initialized->Available->Available->Available->Available
	RedPowerLogic [RP Logic] (redpowerdigital.zip) Unloaded->Constructed->Pre-initialized->Initialized->Post-initialized->Available->Available->Available->Available
	RedPowerLighting [RP Lighting] (redpowerdigital.zip) Unloaded->Constructed->Pre-initialized->Initialized->Post-initialized->Available->Available->Available->Available
	RedPowerWorld [RP World] (redpowermechanical.zip) Unloaded->Constructed->Pre-initialized->Initialized->Post-initialized->Available->Available->Available->Available
	RedPowerControl [RP Control] (redpowermechanical.zip) Unloaded->Constructed->Pre-initialized->Initialized->Post-initialized->Available->Available->Available->Available
	mod_ReiMinimap [mod_ReiMinimap] (reiminimap.zip) Unloaded->Constructed->Pre-initialized->Initialized->Post-initialized->Available->Available->Available->Available
	SoulShards [SoulShards] (soulshards.zip) Unloaded->Constructed->Pre-initialized->Initialized->Post-initialized->Available->Available->Available->Available
	StevesCarts [Steve's Carts] (StevesCarts.zip) Unloaded->Constructed->Pre-initialized->Initialized->Post-initialized->Available->Available->Available->Available
	Thaumcraft [Thaumcraft] (Thaumcraft.zip) Unloaded->Constructed->Pre-initialized->Initialized->Post-initialized->Available->Available->Available->Available
	ThaumicBees [ThaumicBees] (ThaumicBees.jar) Unloaded->Constructed->Pre-initialized->Initialized->Post-initialized->Available->Available->Available->Available
	ThermalExpansion|Factory [Factory] (thermalexpansion.zip) Unloaded->Constructed->Pre-initialized->Initialized->Post-initialized->Available->Available->Available->Available
	ThermalExpansion|Energy [Energy] (thermalexpansion.zip) Unloaded->Constructed->Pre-initialized->Initialized->Post-initialized->Available->Available->Available->Available
	ThermalExpansion|Transport [Transport] (thermalexpansion.zip) Unloaded->Constructed->Pre-initialized->Initialized->Post-initialized->Available->Available->Available->Available
	TwilightForest [The Twilight Forest] (TwilightForest.zip) Unloaded->Constructed->Pre-initialized->Initialized->Post-initialized->Available->Available->Available->Available
	WR-CBE|Core [WR-CBE Core] (wirelessredstonecore.jar) Unloaded->Constructed->Pre-initialized->Initialized->Post-initialized->Available->Available->Available->Available
	WR-CBE|Addons [WR-CBE Addons] (wirelessredstoneaddons.jar) Unloaded->Constructed->Pre-initialized->Initialized->Post-initialized->Available->Available->Available->Available
	WR-CBE|RedPower [WR-CBE RedPower] (wirelessredstoneredpower.jar) Unloaded->Constructed->Pre-initialized->Initialized->Post-initialized->Available->Available->Available->Available
	XReliquary [Xeno's Reliquary] (XReliquary.jar) Unloaded->Constructed->Pre-initialized->Initialized->Post-initialized->Available->Available->Available->Available
	XyCraft [§3XyCraft] (xycraft.zip) Unloaded->Constructed->Pre-initialized->Initialized->Post-initialized->Available->Available->Available->Available
	XyCraftWorld [§2XyCraft World] (xycraft.zip) Unloaded->Constructed->Pre-initialized->Initialized->Post-initialized->Available->Available->Available->Available
	XyCraftMachines [§9XyCraft Machines] (xycraft.zip) Unloaded->Constructed->Pre-initialized->Initialized->Post-initialized->Available->Available->Available->Available
	Profiler Position: N/A (disabled)
	Vec3 Pool Size: 1002 (56112 bytes; 0 MB) allocated, 909 (50904 bytes; 0 MB) used
	Player Count: 1 / 8; [iq['NdMSnIpEz'/274, l='Direwolf20 Lets Play', x=352.53, y=63.00, z=264.42]]
	Type: Integrated Server (map_client.txt)
	Is Modded: Definitely; Client brand changed to 'forge,fml'