Hopper: java.util.ConcurrentModificationException

java.util.ConcurrentModificationException
	at java.util.HashMap$HashIterator.nextEntry(Unknown Source)
	at java.util.HashMap$EntryIterator.next(Unknown Source)
	at java.util.HashMap$EntryIterator.next(Unknown Source)
	at java.util.HashMap.putAllForCreate(Unknown Source)
	at java.util.HashMap.<init>(Unknown Source)
	at blv.b(SourceFile:52)
	at blv.e(SourceFile:209)

---- Minecraft Crash Report ----
// Sorry :(

Time: 9/19/13 6:33 PM
Description: Unexpected error

java.util.ConcurrentModificationException
	at java.util.HashMap$HashIterator.nextEntry(Unknown Source)
	at java.util.HashMap$EntryIterator.next(Unknown Source)
	at java.util.HashMap$EntryIterator.next(Unknown Source)
	at java.util.HashMap.putAllForCreate(Unknown Source)
	at java.util.HashMap.<init>(Unknown Source)
	at blv.b(SourceFile:52)
	at blv.e(SourceFile:209)
	at atv.k(SourceFile:1129)
	at atv.S(SourceFile:663)
	at atv.d(SourceFile:619)
	at net.minecraft.client.main.Main.main(SourceFile:101)


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

-- Head --
Stacktrace:
	at java.util.HashMap$HashIterator.nextEntry(Unknown Source)
	at java.util.HashMap$EntryIterator.next(Unknown Source)
	at java.util.HashMap$EntryIterator.next(Unknown Source)
	at java.util.HashMap.putAllForCreate(Unknown Source)
	at java.util.HashMap.<init>(Unknown Source)
	at blv.b(SourceFile:52)
	at blv.e(SourceFile:209)

-- Affected level --
Details:
	Level name: MpServer
	All players: 1 total; [bdi['failscorpion'/65606, l='MpServer', x=138.84, y=65.62, z=224.50]]
	Chunk stats: MultiplayerChunkCache: 441
	Level seed: 0
	Level generator: ID 00 - default, ver 1. Features enabled: false
	Level generator options: 
	Level spawn location: World: (8,64,8), Chunk: (at 8,4,8 in 0,0; contains blocks 0,0,0 to 15,255,15), Region: (0,0; contains chunks 0,0 to 31,31, blocks 0,0,0 to 511,255,511)
	Level time: 1116186 game time, 26960 day time
	Level dimension: 0
	Level storage version: 0x00000 - Unknown?
	Level weather: Rain time: 0 (now: false), thunder time: 0 (now: false)
	Level game mode: Game mode: survival (ID 0). Hardcore: false. Cheats: false
	Forced entities: 189 total; [tf['Creeper'/3322216, l='MpServer', x=102.50, y=18.00, z=298.50], tw['Zombie'/3322212, l='MpServer', x=104.50, y=18.00, z=300.50], tt['Spider'/3324384, l='MpServer', x=85.47, y=16.00, z=179.56], tt['Spider'/3324386, l='MpServer', x=89.50, y=16.00, z=176.50], tt['Spider'/3324867, l='MpServer', x=97.50, y=19.00, z=285.50], rz['Sheep'/65542, l='MpServer', x=218.97, y=64.00, z=301.03], rq['Chicken'/2891039, l='MpServer', x=158.69, y=61.00, z=200.41], rq['Chicken'/2888656, l='MpServer', x=164.84, y=61.00, z=203.84], tr['Skeleton'/3324913, l='MpServer', x=126.50, y=16.00, z=296.50], ss['item.item.egg'/3228601, l='MpServer', x=163.22, y=61.13, z=203.69], ss['item.item.egg'/3312264, l='MpServer', x=161.56, y=61.13, z=202.78], tf['Creeper'/3324382, l='MpServer', x=84.06, y=16.00, z=179.72], tf['Creeper'/3324923, l='MpServer', x=151.50, y=36.00, z=271.50], tf['Creeper'/3324909, l='MpServer', x=194.50, y=15.00, z=175.50], tf['Creeper'/3323711, l='MpServer', x=109.50, y=37.00, z=300.50], tf['Creeper'/3324907, l='MpServer', x=197.69, y=39.00, z=175.03], tf['Creeper'/3324906, l='MpServer', x=200.50, y=39.00, z=169.50], tw['Zombie'/3323719, l='MpServer', x=105.50, y=25.00, z=284.50], ss['item.item.egg'/3252736, l='MpServer', x=157.19, y=61.13, z=200.03], ss['item.item.egg'/3324837, l='MpServer', x=159.22, y=61.13, z=200.63], tw['Zombie'/3321558, l='MpServer', x=210.97, y=17.00, z=175.50], tr['Skeleton'/3323779, l='MpServer', x=134.50, y=25.00, z=281.50], rq['Chicken'/2890735, l='MpServer', x=161.72, y=61.00, z=200.41], ss['item.item.egg'/2928105, l='MpServer', x=156.66, y=61.13, z=201.56], tf['Creeper'/3319898, l='MpServer', x=127.50, y=20.00, z=287.50], tf['Creeper'/3319899, l='MpServer', x=126.50, y=20.00, z=287.50], ss['item.item.egg'/3275765, l='MpServer', x=164.09, y=61.13, z=200.28], rq['Chicken'/2888550, l='MpServer', x=163.34, y=61.00, z=199.80], tw['Zombie'/3320859, l='MpServer', x=201.50, y=21.00, z=267.50], tf['Creeper'/3324793, l='MpServer', x=101.50, y=23.00, z=286.50], tr['Skeleton'/3325202, l='MpServer', x=120.50, y=30.00, z=273.50], tr['Skeleton'/3325201, l='MpServer', x=121.50, y=30.00, z=275.50], tr['Skeleton'/3325752, l='MpServer', x=173.50, y=14.00, z=164.50], rq['Chicken'/2891676, l='MpServer', x=156.16, y=61.00, z=200.83], rq['Chicken'/2891677, l='MpServer', x=156.78, y=61.00, z=200.66], rq['Chicken'/2891678, l='MpServer', x=156.15, y=61.00, z=199.15], rq['Chicken'/2891679, l='MpServer', x=163.65, y=61.00, z=200.36], tf['Creeper'/3323825, l='MpServer', x=131.50, y=25.00, z=284.50], ss['item.item.egg'/3324230, l='MpServer', x=158.53, y=61.13, z=203.44], ss['item.item.bone'/3320897, l='MpServer', x=153.19, y=61.13, z=198.22], ro['Bat'/3323852, l='MpServer', x=100.66, y=20.42, z=289.49], ro['Bat'/3324702, l='MpServer', x=144.97, y=36.10, z=270.09], tf['Creeper'/3325777, l='MpServer', x=216.50, y=19.00, z=159.50], tr['Skeleton'/3313196, l='MpServer', x=123.50, y=30.00, z=274.50], tw['Zombie'/3325287, l='MpServer', x=126.50, y=24.00, z=302.50], tw['Zombie'/3325288, l='MpServer', x=124.50, y=24.00, z=294.50], tf['Creeper'/3325775, l='MpServer', x=216.50, y=19.00, z=162.50], ry['Pig'/65277, l='MpServer', x=88.50, y=70.00, z=169.69], ss['item.item.egg'/3225640, l='MpServer', x=162.97, y=61.13, z=202.69], rz['Sheep'/65291, l='MpServer', x=122.88, y=70.00, z=152.06], rr['Cow'/65293, l='MpServer', x=116.63, y=67.00, z=161.41], rz['Sheep'/65292, l='MpServer', x=125.47, y=66.00, z=161.97], rq['Chicken'/2890781, l='MpServer', x=164.85, y=61.00, z=199.67], rz['Sheep'/65301, l='MpServer', x=137.47, y=64.00, z=155.97], rz['Sheep'/65302, l='MpServer', x=120.19, y=81.00, z=182.78], ss['item.item.egg'/3324639, l='MpServer', x=162.63, y=61.13, z=200.59], tw['Zombie'/3321275, l='MpServer', x=138.50, y=34.00, z=240.50], rq['Chicken'/65321, l='MpServer', x=161.41, y=61.00, z=202.41], rq['Chicken'/65327, l='MpServer', x=163.28, y=61.00, z=199.16], rq['Chicken'/65326, l='MpServer', x=162.00, y=61.00, z=199.16], rq['Chicken'/65325, l='MpServer', x=164.29, y=61.00, z=199.15], ss['item.item.egg'/3242830, l='MpServer', x=163.41, y=61.13, z=199.13], rq['Chicken'/65324, l='MpServer', x=163.28, y=61.00, z=201.94], rq['Chicken'/65330, l='MpServer', x=164.00, y=61.00, z=199.65], rq['Chicken'/65331, l='MpServer', x=157.07, y=61.00, z=203.85], rq['Chicken'/65328, l='MpServer', x=164.85, y=61.00, z=202.30], rq['Chicken'/65329, l='MpServer', x=156.70, y=61.00, z=199.15], rq['Chicken'/65334, l='MpServer', x=163.44, y=61.00, z=201.41], rq['Chicken'/65335, l='MpServer', x=160.81, y=61.00, z=202.78], rq['Chicken'/65332, l='MpServer', x=164.14, y=61.00, z=200.36], rq['Chicken'/65333, l='MpServer', x=159.94, y=61.00, z=203.84], rq['Chicken'/65338, l='MpServer', x=162.88, y=61.00, z=202.59], rq['Chicken'/65339, l='MpServer', x=157.75, y=61.00, z=203.84], rq['Chicken'/65336, l='MpServer', x=163.28, y=61.00, z=203.84], rq['Chicken'/65337, l='MpServer', x=159.53, y=61.00, z=203.31], rq['Chicken'/65342, l='MpServer', x=159.28, y=61.00, z=200.09], rq['Chicken'/65343, l='MpServer', x=163.10, y=61.00, z=200.86], rq['Chicken'/65340, l='MpServer', x=162.28, y=61.00, z=200.38], rq['Chicken'/65341, l='MpServer', x=156.15, y=61.00, z=200.29], tf['Creeper'/3324071, l='MpServer', x=107.06, y=49.00, z=274.41], rz['Sheep'/65348, l='MpServer', x=159.53, y=65.00, z=293.53], rz['Sheep'/65347, l='MpServer', x=159.66, y=57.00, z=292.50], rq['Chicken'/65357, l='MpServer', x=164.75, y=61.73, z=200.47], rz['Sheep'/65352, l='MpServer', x=181.31, y=73.00, z=149.31], tf['Creeper'/3324072, l='MpServer', x=108.06, y=49.00, z=275.59], rq['Chicken'/65366, l='MpServer', x=162.96, y=61.00, z=200.33], rq['Chicken'/65367, l='MpServer', x=162.63, y=61.00, z=203.53], rq['Chicken'/65362, l='MpServer', x=162.22, y=61.00, z=201.00], ss['item.item.egg'/3282718, l='MpServer', x=158.78, y=61.13, z=199.38], rq['Chicken'/65372, l='MpServer', x=161.63, y=61.00, z=200.88], rq['Chicken'/65373, l='MpServer', x=163.94, y=61.00, z=203.32], tw['Zombie'/3323470, l='MpServer', x=122.50, y=18.00, z=286.50], tt['Spider'/3323471, l='MpServer', x=147.50, y=23.00, z=302.50], rq['Chicken'/65375, l='MpServer', x=157.40, y=61.00, z=199.15], rq['Chicken'/65368, l='MpServer', x=162.72, y=61.00, z=201.38], rq['Chicken'/65369, l='MpServer', x=156.16, y=61.00, z=201.38], rq['Chicken'/65370, l='MpServer', x=164.51, y=61.00, z=199.66], ss['item.item.egg'/3232743, l='MpServer', x=161.03, y=61.13, z=200.59], rq['Chicken'/65383, l='MpServer', x=159.00, y=61.00, z=203.31], rq['Chicken'/65382, l='MpServer', x=161.34, y=61.00, z=199.16], rq['Chicken'/65381, l='MpServer', x=162.22, y=61.00, z=203.03], rq['Chicken'/65380, l='MpServer', x=164.85, y=61.00, z=199.15], ro['Bat'/3321819, l='MpServer', x=112.64, y=19.09, z=301.64], rq['Chicken'/65379, l='MpServer', x=157.63, y=61.00, z=203.31], rq['Chicken'/65378, l='MpServer', x=156.69, y=61.00, z=199.77], rq['Chicken'/65377, l='MpServer', x=162.19, y=61.00, z=202.09], rq['Chicken'/65376, l='MpServer', x=156.24, y=61.00, z=203.29], ry['Pig'/65391, l='MpServer', x=169.19, y=64.00, z=232.79], ry['Pig'/65390, l='MpServer', x=168.08, y=64.00, z=234.86], ry['Pig'/65389, l='MpServer', x=172.43, y=64.00, z=232.41], rq['Chicken'/65388, l='MpServer', x=156.24, y=61.00, z=199.72], rq['Chicken'/65387, l='MpServer', x=156.81, y=61.00, z=203.24], rq['Chicken'/65386, l='MpServer', x=161.34, y=61.00, z=199.78], rq['Chicken'/65385, l='MpServer', x=156.98, y=61.00, z=202.02], rq['Chicken'/65384, l='MpServer', x=156.16, y=61.00, z=202.08], ss['item.item.egg'/3322410, l='MpServer', x=157.34, y=61.13, z=199.16], ry['Pig'/65398, l='MpServer', x=173.83, y=64.00, z=233.53], ry['Pig'/65399, l='MpServer', x=168.89, y=64.00, z=230.93], ry['Pig'/65396, l='MpServer', x=173.27, y=64.00, z=231.14], ss['item.item.egg'/3240847, l='MpServer', x=156.94, y=61.13, z=203.41], ss['item.item.egg'/3234641, l='MpServer', x=157.44, y=61.13, z=202.69], ry['Pig'/65397, l='MpServer', x=170.82, y=64.00, z=231.14], tw['Zombie'/3319634, l='MpServer', x=133.50, y=19.00, z=277.50], ry['Pig'/65394, l='MpServer', x=169.74, y=64.00, z=231.16], ry['Pig'/65395, l='MpServer', x=172.58, y=64.00, z=233.64], ry['Pig'/65392, l='MpServer', x=174.86, y=64.00, z=233.52], ry['Pig'/65393, l='MpServer', x=174.86, y=64.00, z=234.54], ry['Pig'/65406, l='MpServer', x=165.45, y=64.00, z=232.80], ry['Pig'/65407, l='MpServer', x=169.37, y=64.00, z=234.84], ry['Pig'/65404, l='MpServer', x=170.60, y=64.00, z=233.71], ry['Pig'/65405, l='MpServer', x=174.55, y=64.00, z=231.14], ry['Pig'/65402, l='MpServer', x=169.73, y=64.00, z=232.44], ry['Pig'/65403, l='MpServer', x=167.46, y=64.00, z=231.07], ry['Pig'/65400, l='MpServer', x=165.45, y=64.00, z=231.14], ry['Pig'/65401, l='MpServer', x=171.70, y=64.00, z=233.42], ry['Pig'/65416, l='MpServer', x=174.86, y=64.00, z=232.27], ry['Pig'/65417, l='MpServer', x=169.42, y=64.00, z=233.63], ss['item.item.egg'/3265602, l='MpServer', x=160.44, y=61.13, z=199.13], ry['Pig'/65408, l='MpServer', x=171.50, y=64.00, z=234.84], tr['Skeleton'/3324975, l='MpServer', x=214.50, y=17.00, z=149.50], ry['Pig'/65409, l='MpServer', x=174.09, y=64.00, z=234.86], ry['Pig'/65410, l='MpServer', x=172.57, y=64.00, z=234.85], tr['Skeleton'/3324973, l='MpServer', x=212.50, y=17.00, z=150.50], ry['Pig'/65411, l='MpServer', x=173.67, y=64.00, z=232.44], ry['Pig'/65412, l='MpServer', x=172.16, y=64.00, z=231.14], ry['Pig'/65413, l='MpServer', x=166.45, y=64.00, z=232.20], ry['Pig'/65414, l='MpServer', x=167.22, y=64.00, z=233.66], ry['Pig'/65415, l='MpServer', x=171.02, y=64.00, z=232.36], tt['Spider'/3325460, l='MpServer', x=129.47, y=7.31, z=209.72], rr['Cow'/65436, l='MpServer', x=178.13, y=64.00, z=234.16], rr['Cow'/65439, l='MpServer', x=176.50, y=64.00, z=231.16], tf['Creeper'/3325462, l='MpServer', x=135.50, y=8.00, z=208.50], ss['item.item.egg'/3282911, l='MpServer', x=156.38, y=61.13, z=199.59], rr['Cow'/65450, l='MpServer', x=183.31, y=64.00, z=231.16], rr['Cow'/65451, l='MpServer', x=176.16, y=64.00, z=236.50], rr['Cow'/65448, l='MpServer', x=187.84, y=64.00, z=233.91], rr['Cow'/65449, l='MpServer', x=179.53, y=64.00, z=231.09], rr['Cow'/65455, l='MpServer', x=183.38, y=64.00, z=232.41], rr['Cow'/65453, l='MpServer', x=182.50, y=64.00, z=237.19], rr['Cow'/65442, l='MpServer', x=186.94, y=64.00, z=232.38], rr['Cow'/65443, l='MpServer', x=187.25, y=64.00, z=236.78], rr['Cow'/65440, l='MpServer', x=185.75, y=64.00, z=231.16], bdi['failscorpion'/65606, l='MpServer', x=138.84, y=65.62, z=224.50], rr['Cow'/65446, l='MpServer', x=177.06, y=64.00, z=232.38], rr['Cow'/65447, l='MpServer', x=182.13, y=64.00, z=233.22], rr['Cow'/65444, l='MpServer', x=184.56, y=64.00, z=232.31], rr['Cow'/65445, l='MpServer', x=181.56, y=64.00, z=234.50], ro['Bat'/3324542, l='MpServer', x=143.34, y=32.79, z=284.94], ro['Bat'/3323995, l='MpServer', x=132.22, y=18.10, z=299.97], rr['Cow'/65457, l='MpServer', x=187.53, y=64.00, z=231.16], rr['Cow'/65456, l='MpServer', x=185.59, y=64.00, z=236.03], rz['Sheep'/65461, l='MpServer', x=168.22, y=66.00, z=274.19], rz['Sheep'/65460, l='MpServer', x=189.50, y=73.00, z=287.50], rz['Sheep'/65484, l='MpServer', x=205.50, y=63.00, z=302.13], rz['Sheep'/65482, l='MpServer', x=206.50, y=64.00, z=267.69], tr['Skeleton'/3325518, l='MpServer', x=108.03, y=49.00, z=273.46], tr['Skeleton'/3325523, l='MpServer', x=108.50, y=49.00, z=272.50], tr['Skeleton'/3325522, l='MpServer', x=107.44, y=49.00, z=276.56], ss['item.item.egg'/3282366, l='MpServer', x=158.91, y=61.13, z=201.50], ub['Villager'/65516, l='MpServer', x=218.50, y=62.00, z=173.28], ub['Villager'/65517, l='MpServer', x=215.69, y=63.00, z=170.71], ub['Villager'/65514, l='MpServer', x=217.53, y=62.00, z=174.13], ub['Villager'/65515, l='MpServer', x=215.69, y=63.00, z=169.30], ub['Villager'/65509, l='MpServer', x=219.44, y=62.00, z=170.88], rz['Sheep'/65527, l='MpServer', x=214.53, y=63.00, z=289.56], rx['Ocelot'/3325563, l='MpServer', x=174.50, y=66.00, z=152.50], rz['Sheep'/65522, l='MpServer', x=217.91, y=69.00, z=205.09], ub['Villager'/65521, l='MpServer', x=211.69, y=61.00, z=183.94], ub['Villager'/65520, l='MpServer', x=210.72, y=61.00, z=183.31]]
	Retry entities: 0 total; []
	Server brand: vanilla
	Server type: Integrated singleplayer server
Stacktrace:
	at bdd.a(SourceFile:284)
	at atv.b(SourceFile:1761)
	at atv.d(SourceFile:633)
	at net.minecraft.client.main.Main.main(SourceFile:101)

-- System Details --
Details:
	Minecraft Version: 1.6.4
	Operating System: Windows 8 (amd64) version 6.2
	Java Version: 1.7.0_25, Oracle Corporation
	Java VM Version: Java HotSpot(TM) 64-Bit Server VM (mixed mode), Oracle Corporation
	Memory: 72392624 bytes (69 MB) / 291897344 bytes (278 MB) up to 954466304 bytes (910 MB)
	JVM Flags: 2 total; -XX:HeapDumpPath=MojangTricksIntelDriversForPerformance_javaw.exe_minecraft.exe.heapdump -Xmx1G
	AABB Pool Size: 3125 (175000 bytes; 0 MB) allocated, 0 (0 bytes; 0 MB) used
	Suspicious classes: No suspicious classes found.
	IntCache: cache: 0, tcache: 0, allocated: 1, tallocated: 63
	Launched Version: 1.6.4
	LWJGL: 2.9.0
	OpenGL: Intel(R) HD Graphics GL version 4.0.0 - Build 9.17.10.2932, Intel
	Is Modded: Probably not. Jar signature remains and client brand is untouched.
	Type: Client (map_client.txt)
	Resource Pack: Default
	Current Language: English (US)
	Profiler Position: N/A (disabled)
	Vec3 Pool Size: 523 (29288 bytes; 0 MB) allocated, 0 (0 bytes; 0 MB) used