Hopper: java.lang.NullPointerException: Updating screen events

java.lang.NullPointerException: Updating screen events
	at awz.b(SourceFile:38)
	at bce.h(SourceFile:80)
	at bce.r_(SourceFile:59)
	at bcd.a(SourceFile:197)
	at azd.a(SourceFile:641)
	at btj.a(SourceFile:265)
	at bcd.a(SourceFile:172)
	at btj.a(SourceFile:517)
	at bcd.d(SourceFile:236)
	at bcd.k(SourceFile:211)

---- Minecraft Crash Report ----
// There are four lights!

Time: 25-10-13 15:57
Description: Updating screen events

java.lang.NullPointerException: Updating screen events
	at awz.b(SourceFile:38)
	at bce.h(SourceFile:80)
	at bce.r_(SourceFile:59)
	at bcd.a(SourceFile:197)
	at azd.a(SourceFile:641)
	at btj.a(SourceFile:265)
	at bcd.a(SourceFile:172)
	at btj.a(SourceFile:517)
	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 awz.b(SourceFile:38)
	at bce.h(SourceFile:80)
	at bce.r_(SourceFile:59)
	at bcd.a(SourceFile:197)
	at azd.a(SourceFile:641)
	at btj.a(SourceFile:265)
	at bcd.a(SourceFile:172)
	at btj.a(SourceFile:517)
	at bcd.d(SourceFile:236)
	at bcd.k(SourceFile:211)

-- Affected screen --
Details:
	Screen name: bce
Stacktrace:
	at azd.o(SourceFile:1303)
	at azd.ad(SourceFile:753)
	at azd.e(SourceFile:704)
	at net.minecraft.client.main.Main.main(SourceFile:103)

-- System Details --
Details:
	Minecraft Version: 1.7.2
	Operating System: Windows 8 (x86) version 6.2
	Java Version: 1.7.0_45, Oracle Corporation
	Java VM Version: Java HotSpot(TM) Client VM (mixed mode), Oracle Corporation
	Memory: 185747168 bytes (177 MB) / 309903360 bytes (295 MB) up to 1060372480 bytes (1011 MB)
	JVM Flags: 3 total; -XX:HeapDumpPath=MojangTricksIntelDriversForPerformance_javaw.exe_minecraft.exe.heapdump -Xincgc -Xmx1024M
	AABB Pool Size: 24850 (1391600 bytes; 1 MB) allocated, 0 (0 bytes; 0 MB) used
	IntCache: cache: 0, tcache: 0, allocated: 13, tallocated: 95
	Launched Version: 1.7.2
	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 Packs: []
	Current Language: English (US)
	Profiler Position: N/A (disabled)
	Vec3 Pool Size: ~~ERROR~~ NullPointerException: null
	Anisotropic Filtering: Off (1)