Hopper: java.lang.NullPointerException

java.lang.NullPointerException
	at va.e(SourceFile:199)
	at va.a(SourceFile:123)
	at vb.e(SourceFile:38)
	at mu.a(SourceFile:68)
	at we.c(SourceFile:77)
	at uy.a(SourceFile:223)
	at bdc.a(SourceFile:295)
	at awy.a(SourceFile:582)
	at awy.b(SourceFile:555)
	at awe.d(SourceFile:132)
	at awe.m(SourceFile:107)

---- Minecraft Crash Report ----
// Hey, that tickles! Hehehe!

Time: 22:59 19/09/13
Description: Updating screen events

java.lang.NullPointerException
	at va.e(SourceFile:199)
	at va.a(SourceFile:123)
	at vb.e(SourceFile:38)
	at mu.a(SourceFile:68)
	at we.c(SourceFile:77)
	at uy.a(SourceFile:223)
	at bdc.a(SourceFile:295)
	at awy.a(SourceFile:582)
	at awy.b(SourceFile:555)
	at awe.d(SourceFile:132)
	at awe.m(SourceFile:107)
	at atv.k(SourceFile:1158)
	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 va.e(SourceFile:199)
	at va.a(SourceFile:123)
	at vb.e(SourceFile:38)
	at mu.a(SourceFile:68)
	at we.c(SourceFile:77)
	at uy.a(SourceFile:223)
	at bdc.a(SourceFile:295)
	at awy.a(SourceFile:582)
	at awy.b(SourceFile:555)
	at awe.d(SourceFile:132)
	at awe.m(SourceFile:107)

-- Affected screen --
Details:
	Screen name: awz

-- Affected level --
Details:
	Level name: MpServer
	All players: 1 total; [bdi['MishmishTNT'/246, l='MpServer', x=219.50, y=85.62, z=255.26]]
	Chunk stats: MultiplayerChunkCache: 441
	Level seed: 0
	Level generator: ID 00 - default, ver 1. Features enabled: false
	Level generator options: 
	Level spawn location: World: (124,64,240), Chunk: (at 12,4,0 in 7,15; contains blocks 112,0,240 to 127,255,255), Region: (0,0; contains chunks 0,0 to 31,31, blocks 0,0,0 to 511,255,511)
	Level time: 439732 game time, 79160 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: creative (ID 1). Hardcore: false. Cheats: false
	Forced entities: 81 total; [tw['Zombie'/7888, l='MpServer', x=268.50, y=25.00, z=315.50], tt['Spider'/7891, l='MpServer', x=265.00, y=26.02, z=312.72], tw['Zombie'/139, l='MpServer', x=188.00, y=49.00, z=329.56], ro['Bat'/138, l='MpServer', x=217.58, y=28.85, z=285.38], tr['Skeleton'/8135, l='MpServer', x=197.50, y=50.00, z=191.50], tw['Zombie'/7775, l='MpServer', x=169.00, y=17.00, z=258.44], tr['Skeleton'/8138, l='MpServer', x=240.50, y=42.00, z=335.50], tr['Skeleton'/8139, l='MpServer', x=239.50, y=42.00, z=335.50], tw['Zombie'/7421, l='MpServer', x=236.50, y=44.00, z=303.50], tw['Zombie'/6443, l='MpServer', x=158.59, y=21.00, z=275.06], tr['Skeleton'/6442, l='MpServer', x=160.50, y=21.00, z=269.50], tf['Creeper'/8512, l='MpServer', x=156.50, y=24.00, z=240.50], tr['Skeleton'/157, l='MpServer', x=233.84, y=43.00, z=268.25], tt['Spider'/8514, l='MpServer', x=176.50, y=27.00, z=287.50], ss['item.item.rottenFlesh'/158, l='MpServer', x=227.72, y=64.13, z=289.13], tw['Zombie'/8650, l='MpServer', x=237.50, y=13.00, z=288.50], tw['Zombie'/159, l='MpServer', x=235.88, y=17.00, z=319.28], tf['Creeper'/8645, l='MpServer', x=240.50, y=13.00, z=310.50], tf['Creeper'/8018, l='MpServer', x=272.50, y=42.00, z=274.50], tf['Creeper'/8019, l='MpServer', x=274.50, y=42.00, z=269.50], tf['Creeper'/8647, l='MpServer', x=243.50, y=13.00, z=312.50], tf['Creeper'/8646, l='MpServer', x=244.50, y=13.00, z=312.50], tr['Skeleton'/149, l='MpServer', x=210.50, y=31.00, z=297.50], tf['Creeper'/8020, l='MpServer', x=273.50, y=42.00, z=269.50], bdi['MishmishTNT'/246, l='MpServer', x=219.50, y=85.62, z=255.26], tf['Creeper'/8021, l='MpServer', x=270.97, y=42.00, z=270.66], ro['Bat'/151, l='MpServer', x=213.75, y=32.10, z=290.25], tf['Creeper'/171, l='MpServer', x=243.50, y=63.00, z=286.70], ro['Bat'/8162, l='MpServer', x=195.43, y=43.00, z=271.27], tf['Creeper'/9042, l='MpServer', x=286.50, y=32.00, z=201.50], ro['Bat'/7927, l='MpServer', x=241.25, y=37.10, z=281.25], ro['Bat'/175, l='MpServer', x=256.28, y=25.33, z=287.80], ro['Bat'/6707, l='MpServer', x=189.70, y=53.53, z=188.13], ro['Bat'/173, l='MpServer', x=258.38, y=26.10, z=303.75], tw['Zombie'/161, l='MpServer', x=222.78, y=24.00, z=320.88], tr['Skeleton'/7793, l='MpServer', x=246.50, y=44.00, z=263.50], tw['Zombie'/164, l='MpServer', x=228.50, y=21.00, z=320.50], rz['Sheep'/186, l='MpServer', x=263.53, y=76.00, z=216.38], rz['Sheep'/187, l='MpServer', x=258.66, y=64.00, z=261.66], tw['Zombie'/7791, l='MpServer', x=166.63, y=17.00, z=258.47], tt['Spider'/190, l='MpServer', x=264.50, y=11.00, z=293.13], ro['Bat'/8436, l='MpServer', x=287.90, y=22.85, z=322.25], tr['Skeleton'/7778, l='MpServer', x=164.78, y=18.00, z=257.66], tf['Creeper'/9034, l='MpServer', x=264.50, y=37.00, z=286.50], tr['Skeleton'/7777, l='MpServer', x=164.50, y=18.00, z=255.50], tf['Creeper'/9035, l='MpServer', x=263.50, y=37.00, z=288.50], tw['Zombie'/7776, l='MpServer', x=164.50, y=18.00, z=258.56], tf['Creeper'/9036, l='MpServer', x=263.50, y=37.00, z=285.50], ro['Bat'/7916, l='MpServer', x=157.36, y=14.02, z=180.78], tw['Zombie'/9039, l='MpServer', x=155.50, y=26.00, z=247.50], ro['Bat'/8467, l='MpServer', x=146.43, y=29.00, z=245.25], tr['Skeleton'/70, l='MpServer', x=141.44, y=15.00, z=256.44], tf['Creeper'/8592, l='MpServer', x=254.50, y=20.00, z=311.50], tf['Creeper'/197, l='MpServer', x=263.59, y=24.00, z=316.69], rz['Sheep'/196, l='MpServer', x=262.31, y=70.00, z=301.91], tw['Zombie'/7940, l='MpServer', x=174.50, y=26.00, z=271.50], tf['Creeper'/8325, l='MpServer', x=260.50, y=46.00, z=330.50], tf['Creeper'/8324, l='MpServer', x=261.50, y=46.00, z=329.50], tf['Creeper'/194, l='MpServer', x=248.44, y=44.00, z=293.28], sc['Squid'/7685, l='MpServer', x=157.94, y=57.34, z=300.34], tw['Zombie'/7821, l='MpServer', x=249.50, y=27.00, z=297.50], tw['Zombie'/7822, l='MpServer', x=255.06, y=26.00, z=302.50], sc['Squid'/7686, l='MpServer', x=164.50, y=57.31, z=294.50], tf['Creeper'/7006, l='MpServer', x=231.50, y=48.00, z=326.50], tr['Skeleton'/7007, l='MpServer', x=231.50, y=48.00, z=325.50], tr['Skeleton'/7008, l='MpServer', x=231.50, y=48.00, z=327.50], ro['Bat'/7738, l='MpServer', x=226.41, y=26.10, z=332.75], ro['Bat'/7739, l='MpServer', x=187.50, y=45.92, z=269.73], rz['Sheep'/97, l='MpServer', x=168.03, y=64.00, z=264.09], rz['Sheep'/231, l='MpServer', x=297.81, y=66.00, z=225.66], tf['Creeper'/8988, l='MpServer', x=191.50, y=51.00, z=186.50], ro['Bat'/7735, l='MpServer', x=205.83, y=41.30, z=296.34], tf['Creeper'/8991, l='MpServer', x=234.50, y=38.00, z=265.50], tf['Creeper'/108, l='MpServer', x=178.50, y=13.00, z=182.50], tt['Spider'/8990, l='MpServer', x=227.50, y=16.00, z=286.50], rz['Sheep'/109, l='MpServer', x=184.09, y=63.00, z=181.22], tr['Skeleton'/7866, l='MpServer', x=143.06, y=19.00, z=321.50], rz['Sheep'/118, l='MpServer', x=178.88, y=64.00, z=282.03], rz['Sheep'/117, l='MpServer', x=188.50, y=78.00, z=280.50], rz['Sheep'/112, l='MpServer', x=188.81, y=71.00, z=205.22], tr['Skeleton'/121, l='MpServer', x=187.84, y=49.00, z=311.38]]
	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:628)
	at net.minecraft.client.main.Main.main(SourceFile:101)

-- System Details --
Details:
	Minecraft Version: 1.6.4
	Operating System: Windows 8 (x86) version 6.2
	Java Version: 1.7.0_25, Oracle Corporation
	Java VM Version: Java HotSpot(TM) Client VM (mixed mode, sharing), Oracle Corporation
	Memory: 78568432 bytes (74 MB) / 239177728 bytes (228 MB) up to 518979584 bytes (494 MB)
	JVM Flags: 2 total; -XX:HeapDumpPath=MojangTricksIntelDriversForPerformance_javaw.exe_minecraft.exe.heapdump -Xmx512M
	AABB Pool Size: 6241 (349496 bytes; 0 MB) allocated, 2 (112 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 3.1.0 - Build 9.17.10.2828, 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: 2455 (137480 bytes; 0 MB) allocated, 16 (896 bytes; 0 MB) used