---- Minecraft Crash Report ----
// Oops.

Time: 12/29/13 9:01 AM
Description: Exception in server tick loop

java.util.ConcurrentModificationException
	at java.util.HashMap$HashIterator.nextEntry(HashMap.java:926)
	at java.util.HashMap$EntryIterator.next(HashMap.java:966)
	at java.util.HashMap$EntryIterator.next(HashMap.java:964)
	at com.advGenetics.TickHandler.TickHandlerClientServerSync.tickStart(TickHandlerClientServerSync.java:33)
	at za.co.mcportcentral.SkipIntervalHandler.tickStart(SkipIntervalHandler.java:32)
	at cpw.mods.fml.common.FMLCommonHandler.tickStart(FMLCommonHandler.java:122)
	at cpw.mods.fml.common.FMLCommonHandler.onPreWorldTick(FMLCommonHandler.java:295)
	at net.minecraft.server.MinecraftServer.func_71190_q(MinecraftServer.java:883)
	at net.minecraft.server.dedicated.DedicatedServer.func_71190_q(DedicatedServer.java:330)
	at net.minecraft.server.MinecraftServer.func_71217_p(MinecraftServer.java:793)
	at net.minecraft.server.MinecraftServer.run(MinecraftServer.java:675)
	at net.minecraft.server.ThreadMinecraftServer.run(ThreadMinecraftServer.java:16)


A detailed walkthrough of the error, its code path and all known details is as follows:
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-- System Details --
Details:
	Minecraft Version: 1.6.4
	Operating System: Linux (amd64) version 2.6.32-358.14.1.el6.x86_64
	Java Version: 1.7.0_45, Oracle Corporation
	Java VM Version: OpenJDK 64-Bit Server VM (mixed mode), Oracle Corporation
	Memory: 4526376696 bytes (4316 MB) / 8246394880 bytes (7864 MB) up to 13400342528 bytes (12779 MB)
	JVM Flags: 38 total; -Xms8192M -Xmx13312M -XX:PermSize=512m -XX:ReservedCodeCacheSize=512m -XX:NewRatio=4 -XX:SurvivorRatio=3 -XX:TargetSurvivorRatio=80 -XX:MaxTenuringThreshold=8 -XX:+UseParNewGC -XX:+UseConcMarkSweepGC -XX:SoftRefLRUPolicyMSPerMB=0 -XX:MaxGCPauseMillis=20 -XX:GCPauseIntervalMillis=250 -XX:MaxGCMinorPauseMillis=7 -XX:+CMSClassUnloadingEnabled -XX:+ExplicitGCInvokesConcurrentAndUnloadsClasses -XX:+UseCMSInitiatingOccupancyOnly -XX:CMSInitiatingOccupancyFraction=50 -XX:+BindGCTaskThreadsToCPUs -XX:+TieredCompilation -XX:Tier0ProfilingStartPercentage=0 -XX:Tier3InvocationThreshold=3 -XX:Tier3MinInvocationThreshold=2 -XX:Tier3CompileThreshold=2 -XX:Tier3BackEdgeThreshold=10 -XX:Tier4InvocationThreshold=4 -XX:Tier4MinInvocationThreshold=3 -XX:Tier4CompileThreshold=2 -XX:Tier4BackEdgeThreshold=8 -XX:TieredCompileTaskTimeout=5000 -XX:Tier3DelayOn=50 -XX:Tier3DelayOff=25 -XX:+UseFastEmptyMethods -XX:-DontCompileHugeMethods -XX:+AlwaysCompileLoopMethods -XX:+CICompilerCountPerCPU -XX:+UseStringCache -XX:+UseNUMA
	AABB Pool Size: 20448 (1145088 bytes; 1 MB) allocated, 0 (0 bytes; 0 MB) used
	Suspicious classes: FML and Forge are installed