Hopper: java.lang.NullPointerException: Updating screen events

This is an automatically generated report based from the following crash: http://hopper.minecraft.net/crashes/minecraft/MCX-465681/

Crash:

java.lang.NullPointerException: Updating screen events
	at afa.a(SourceFile:36)
	at ze.h(SourceFile:135)
	at ze.a(SourceFile:77)
	at zg.a(SourceFile:66)
	at ye.a(SourceFile:238)
	at biy.a(SourceFile:308)
	at bdd.a(SourceFile:490)
	at bdd.a(SourceFile:318)
	at bcd.d(SourceFile:236)
	at bcd.k(SourceFile:211)

The following is the first clean report made public about this crash:

---- Minecraft Crash Report ----
// Daisy, daisy...

Time: 25/10/13 16:13
Description: Updating screen events

java.lang.NullPointerException: Updating screen events
	at afa.a(SourceFile:36)
	at ze.h(SourceFile:135)
	at ze.a(SourceFile:77)
	at zg.a(SourceFile:66)
	at ye.a(SourceFile:238)
	at biy.a(SourceFile:308)
	at bdd.a(SourceFile:490)
	at bdd.a(SourceFile:318)
	at bcd.d(SourceFile:236)
	at bcd.k(SourceFile:211)
	at azd.o(SourceFile:1303)
	at azd.ad(SourceFile:753)
	at azd.e(SourceFile:704)
	at net.minecraft.client.main.Main.main(SourceFile:103)


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

-- Head --
Stacktrace:
	at afa.a(SourceFile:36)
	at ze.h(SourceFile:135)
	at ze.a(SourceFile:77)
	at zg.a(SourceFile:66)
	at ye.a(SourceFile:238)
	at biy.a(SourceFile:308)
	at bdd.a(SourceFile:490)
	at bdd.a(SourceFile:318)
	at bcd.d(SourceFile:236)
	at bcd.k(SourceFile:211)

-- Affected screen --
Details:
	Screen name: beb

-- Affected level --
Details:
	Level name: MpServer
	All players: 2 total; [bje['Dippy_'/1227818, l='MpServer', x=1001.55, y=65.62, z=-8.70], bld['maryparry2'/1228832, l='MpServer', x=1004.92, y=60.00, z=7.58]]
	Chunk stats: MultiplayerChunkCache: 303, 303
	Level seed: 0
	Level generator: ID 01 - flat, ver 0. Features enabled: false
	Level generator options: 
	Level spawn location: World: (0,64,0), Chunk: (at 0,4,0 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: 812227 game time, 6000 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: 31 total; [bld['maryparry2'/1228832, l='MpServer', x=1004.92, y=60.00, z=7.58], xc['Zombie'/1253690, l='MpServer', x=997.34, y=59.54, z=48.31], bld['maryparry2'/1228832, l='MpServer', x=1004.92, y=60.00, z=7.58], xc['Zombie'/1250440, l='MpServer', x=1003.78, y=60.00, z=11.95], xc['Zombie'/1251925, l='MpServer', x=1007.33, y=60.00, z=24.44], xc['Zombie'/1254878, l='MpServer', x=1004.50, y=56.00, z=59.28], xc['Zombie'/1250965, l='MpServer', x=995.97, y=60.00, z=13.66], xc['Zombie'/1254000, l='MpServer', x=1000.50, y=59.99, z=51.31], xo['arrow'/1252251, l='MpServer', x=991.03, y=60.81, z=14.75], xc['Zombie'/1252250, l='MpServer', x=993.66, y=60.00, z=29.31], xc['Zombie'/1252782, l='MpServer', x=1002.50, y=60.00, z=37.91], xo['arrow'/1252143, l='MpServer', x=992.00, y=60.03, z=13.03], xc['Zombie'/1251300, l='MpServer', x=1007.78, y=60.46, z=17.55], rn['Painting'/1227819, l='MpServer', x=999.50, y=65.50, z=-11.94], rf['entity.ItemFrame.name'/1227820, l='MpServer', x=1002.50, y=65.50, z=-11.94], xh['Crazy Ed'/1227821, l='MpServer', x=1001.00, y=64.00, z=-10.50], bje['Dippy_'/1227818, l='MpServer', x=1001.55, y=65.62, z=-8.70], xh['Villager'/1227823, l='MpServer', x=990.50, y=52.00, z=0.50], xh['Villager'/1227827, l='MpServer', x=1006.50, y=52.00, z=0.50], xh['Villager'/1227826, l='MpServer', x=1004.50, y=52.00, z=0.50], xh['Villager'/1227829, l='MpServer', x=1000.50, y=52.00, z=0.50], xh['Villager'/1227828, l='MpServer', x=1002.50, y=52.00, z=0.50], xh['Villager'/1227831, l='MpServer', x=996.50, y=52.00, z=0.50], xh['Villager'/1227830, l='MpServer', x=998.50, y=52.00, z=0.50], xh['Villager'/1227833, l='MpServer', x=992.50, y=52.00, z=0.50], xh['Villager'/1227832, l='MpServer', x=994.50, y=52.00, z=0.50], xc['Zombie'/1254558, l='MpServer', x=994.50, y=58.00, z=56.61], xh['Villager'/1227885, l='MpServer', x=1010.50, y=52.00, z=0.50], xh['Villager'/1227886, l='MpServer', x=1008.50, y=52.00, z=0.50], rn['Painting'/1227819, l='MpServer', x=999.50, y=65.50, z=-11.94], xc['Zombie'/1253120, l='MpServer', x=1009.50, y=60.00, z=39.95]]
	Retry entities: 0 total; []
	Server brand: vanilla
	Server type: Integrated singleplayer server
Stacktrace:
	at biz.a(SourceFile:284)
	at azd.b(SourceFile:1951)
	at azd.e(SourceFile:713)
	at net.minecraft.client.main.Main.main(SourceFile:103)

-- System Details --
Details:
	Minecraft Version: 1.7.2
	Operating System: Linux (i386) version 3.8.0-31-generic
	Java Version: 1.7.0_25, Oracle Corporation
	Java VM Version: OpenJDK Server VM (mixed mode), Oracle Corporation
	Memory: 60782792 bytes (57 MB) / 452460544 bytes (431 MB) up to 477233152 bytes (455 MB)
	JVM Flags: 1 total; -Xmx512M
	AABB Pool Size: 3034 (169904 bytes; 0 MB) allocated, 5 (280 bytes; 0 MB) used
	IntCache: cache: 0, tcache: 0, allocated: 12, tallocated: 94
	Launched Version: 1.7.2
	LWJGL: 2.9.0
	OpenGL: Gallium 0.4 on AMD CEDAR GL version 3.0 Mesa 9.1.7, X.Org
	Is Modded: Probably not. Jar signature remains and client brand is untouched.
	Type: Client (map_client.txt)
	Resource Packs: []
	Current Language: English (UK)
	Profiler Position: N/A (disabled)
	Vec3 Pool Size: 811 (45416 bytes; 0 MB) allocated, 34 (1904 bytes; 0 MB) used
	Anisotropic Filtering: On (16)

You can see this full report at http://hopper.minecraft.net/crashes/minecraft/MCX-465681/21380360/