[23:07:40] [Server thread/ERROR]: Encountered an unexpected exception
net.minecraft.server.v1_7_R3.ReportedException: Ticking entity
	at net.minecraft.server.v1_7_R3.MinecraftServer.v(MinecraftServer.java:714) ~[spigot.jar:git-Spigot-unknown]
	at net.minecraft.server.v1_7_R3.DedicatedServer.v(DedicatedServer.java:289) ~[spigot.jar:git-Spigot-unknown]
	at net.minecraft.server.v1_7_R3.MinecraftServer.u(MinecraftServer.java:584) ~[spigot.jar:git-Spigot-unknown]
	at net.minecraft.server.v1_7_R3.MinecraftServer.run(MinecraftServer.java:490) [spigot.jar:git-Spigot-unknown]
	at net.minecraft.server.v1_7_R3.ThreadServerApplication.run(SourceFile:628) [spigot.jar:git-Spigot-unknown]
Caused by: java.util.ConcurrentModificationException
	at java.util.HashMap$HashIterator.nextNode(HashMap.java:1429) ~[?:1.8.0_05]
	at java.util.HashMap$KeyIterator.next(HashMap.java:1453) ~[?:1.8.0_05]
	at net.minecraft.server.v1_7_R3.EntityTracker.a(EntityTracker.java:207) ~[spigot.jar:git-Spigot-unknown]
	at net.minecraft.server.v1_7_R3.EntityPlayer.h(EntityPlayer.java:249) ~[spigot.jar:git-Spigot-unknown]
	at net.minecraft.server.v1_7_R3.World.entityJoinedWorld(World.java:1603) ~[spigot.jar:git-Spigot-unknown]
	at net.minecraft.server.v1_7_R3.World.playerJoinedWorld(World.java:1578) ~[spigot.jar:git-Spigot-unknown]
	at net.minecraft.server.v1_7_R3.World.tickEntities(World.java:1443) ~[spigot.jar:git-Spigot-unknown]
	at net.minecraft.server.v1_7_R3.WorldServer.tickEntities(WorldServer.java:516) ~[spigot.jar:git-Spigot-unknown]
	at net.minecraft.server.v1_7_R3.MinecraftServer.v(MinecraftServer.java:703) ~[spigot.jar:git-Spigot-unknown]
	... 4 more
[23:07:40] [Server thread/ERROR]: 	Cause of unexpected exception was
java.util.ConcurrentModificationException
	at java.util.HashMap$HashIterator.nextNode(HashMap.java:1429) ~[?:1.8.0_05]
	at java.util.HashMap$KeyIterator.next(HashMap.java:1453) ~[?:1.8.0_05]
	at net.minecraft.server.v1_7_R3.EntityTracker.a(EntityTracker.java:207) ~[spigot.jar:git-Spigot-unknown]
	at net.minecraft.server.v1_7_R3.EntityPlayer.h(EntityPlayer.java:249) ~[spigot.jar:git-Spigot-unknown]
	at net.minecraft.server.v1_7_R3.World.entityJoinedWorld(World.java:1603) ~[spigot.jar:git-Spigot-unknown]
	at net.minecraft.server.v1_7_R3.World.playerJoinedWorld(World.java:1578) ~[spigot.jar:git-Spigot-unknown]
	at net.minecraft.server.v1_7_R3.World.tickEntities(World.java:1443) ~[spigot.jar:git-Spigot-unknown]
	at net.minecraft.server.v1_7_R3.WorldServer.tickEntities(WorldServer.java:516) ~[spigot.jar:git-Spigot-unknown]
	at net.minecraft.server.v1_7_R3.MinecraftServer.v(MinecraftServer.java:703) ~[spigot.jar:git-Spigot-unknown]
	at net.minecraft.server.v1_7_R3.DedicatedServer.v(DedicatedServer.java:289) ~[spigot.jar:git-Spigot-unknown]
	at net.minecraft.server.v1_7_R3.MinecraftServer.u(MinecraftServer.java:584) ~[spigot.jar:git-Spigot-unknown]
	at net.minecraft.server.v1_7_R3.MinecraftServer.run(MinecraftServer.java:490) [spigot.jar:git-Spigot-unknown]
	at net.minecraft.server.v1_7_R3.ThreadServerApplication.run(SourceFile:628) [spigot.jar:git-Spigot-unknown]
[23:07:40] [Server thread/ERROR]: This crash report has been saved to: /minecraft/prison1/./crash-reports/crash-2014-07-22_23.07.40-server.txt