Hopper: java.lang.NullPointerException

java.lang.NullPointerException
	at bcw.a(SourceFile:1071)
	at eo.a(SourceFile:78)
	at co.b(SourceFile:354)
	at bcw.e(SourceFile:98)
	at bcy.c(SourceFile:71)

---- Minecraft Crash Report ----
// Oops.

Time: 10/16/13 4:23 PM
Description: Ticking screen

java.lang.NullPointerException
	at bcw.a(SourceFile:1071)
	at eo.a(SourceFile:78)
	at co.b(SourceFile:354)
	at bcw.e(SourceFile:98)
	at bcy.c(SourceFile:71)
	at atv.k(SourceFile:1173)
	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 bcw.a(SourceFile:1071)
	at eo.a(SourceFile:78)
	at co.b(SourceFile:354)
	at bcw.e(SourceFile:98)
	at bcy.c(SourceFile:71)

-- Affected screen --
Details:
	Screen name: bda
Stacktrace:
	at atv.k(SourceFile:1173)
	at atv.S(SourceFile:663)
	at atv.d(SourceFile:619)
	at net.minecraft.client.main.Main.main(SourceFile:101)

-- System Details --
Details:
	Minecraft Version: 1.6.4
	Operating System: Mac OS X (x86_64) version 10.8.4
	Java Version: 1.6.0_51, Apple Inc.
	Java VM Version: Java HotSpot(TM) 64-Bit Server VM (mixed mode), Apple Inc.
	Memory: 46410072 bytes (44 MB) / 85000192 bytes (81 MB) up to 1065025536 bytes (1015 MB)
	JVM Flags: 1 total; -Xmx1G
	AABB Pool Size: 10817 (605752 bytes; 0 MB) allocated, 10817 (605752 bytes; 0 MB) used
	Suspicious classes: No suspicious classes found.
	IntCache: cache: 0, tcache: 0, allocated: 0, tallocated: 0
	Launched Version: 1.6.4
	LWJGL: 2.9.0
	OpenGL: NVIDIA GeForce GT 640M OpenGL Engine GL version 2.1 NVIDIA-8.12.47 310.40.00.05f01, NVIDIA Corporation
	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: ~~ERROR~~ NullPointerException: null