Hopper: java.lang.NullPointerException arv.a(SourceFile:197)

This is an automatically generated report based from the following crash: http://hopper.minecraft.net/crashes/minecraft/MCX-5790/

Crash:

java.lang.NullPointerException
	at arv.a(SourceFile:197)
	at arv.j(SourceFile:177)
	at arv.w_(SourceFile:300)
	at abv.a(SourceFile:1658)
	at adq.e(SourceFile:540)
	at adq.a(SourceFile:397)
	at abv.f(SourceFile:306)
	at afo.a(SourceFile:96)
	at aes.a(SourceFile:451)
	at jq.a(SourceFile:168)
	at adq.a(SourceFile:726)
	at jq.c(SourceFile:105)
	at jq.d(SourceFile:116)
	at abv.e(SourceFile:289)

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

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

Time: 6/08/13 12:28 PM
Description: Exception getting block type in world

java.lang.NullPointerException
	at arv.a(SourceFile:197)
	at arv.j(SourceFile:177)
	at arv.w_(SourceFile:300)
	at abv.a(SourceFile:1658)
	at adq.e(SourceFile:540)
	at adq.a(SourceFile:397)
	at abv.f(SourceFile:306)
	at afo.a(SourceFile:96)
	at aes.a(SourceFile:451)
	at jq.a(SourceFile:168)
	at adq.a(SourceFile:726)
	at jq.c(SourceFile:105)
	at jq.d(SourceFile:116)
	at abv.e(SourceFile:289)
	at abv.a(SourceFile:213)
	at arv.a(SourceFile:197)
	at arv.j(SourceFile:183)
	at arv.h(SourceFile:205)
	at abv.h(SourceFile:1267)
	at jr.h(SourceFile:364)
	at net.minecraft.server.MinecraftServer.t(SourceFile:470)
	at net.minecraft.server.MinecraftServer.s(SourceFile:405)
	at bkw.s(SourceFile:124)
	at net.minecraft.server.MinecraftServer.run(SourceFile:339)
	at hh.run(SourceFile:582)


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

-- Head --
Stacktrace:
	at arv.a(SourceFile:197)
	at arv.j(SourceFile:177)
	at arv.w_(SourceFile:300)
	at abv.a(SourceFile:1658)
	at adq.e(SourceFile:540)
	at adq.a(SourceFile:397)
	at abv.f(SourceFile:306)
	at afo.a(SourceFile:96)
	at aes.a(SourceFile:451)
	at jq.a(SourceFile:168)
	at adq.a(SourceFile:726)
	at jq.c(SourceFile:105)
	at jq.d(SourceFile:116)
	at abv.e(SourceFile:289)

-- Requested block coordinates --
Details:
	Found chunk: true
	Location: World: (-1557,23,-881), Chunk: (at 11,1,15 in -98,-56; contains blocks -1568,0,-896 to -1553,255,-881), Region: (-4,-2; contains chunks -128,-64 to -97,-33, blocks -2048,0,-1024 to -1537,255,-513)
Stacktrace:
	at abv.a(SourceFile:213)
	at arv.a(SourceFile:197)
	at arv.j(SourceFile:183)
	at arv.h(SourceFile:205)

-- Tile entity being ticked --
Details:
	Name: Chest // arv
	Block type: ID #54 (tile.chest // anh)
	Block data value: 2 / 0x2 / 0b0010
	Block location: World: (-1557,23,-880), Chunk: (at 11,1,0 in -98,-55; contains blocks -1568,0,-880 to -1553,255,-865), Region: (-4,-2; contains chunks -128,-64 to -97,-33, blocks -2048,0,-1024 to -1537,255,-513)
	Actual block type: ID #54 (tile.chest // anh)
	Actual block data value: 2 / 0x2 / 0b0010
Stacktrace:
	at abv.h(SourceFile:1267)
	at jr.h(SourceFile:364)

-- Affected level --
Details:
	Level name: Hanks world
	All players: 1 total; [ju['KADavis'/284814, l='Hanks world', x=-1739.50, y=68.00, z=-852.70]]
	Chunk stats: ServerChunkCache: 1631 Drop: 0
	Level seed: 6854059799962698590
	Level generator: ID 00 - default, ver 1. Features enabled: true
	Level generator options: 
	Level spawn location: World: (36,64,240), Chunk: (at 4,4,0 in 2,15; contains blocks 32,0,240 to 47,255,255), Region: (0,0; contains chunks 0,0 to 31,31, blocks 0,0,0 to 511,255,511)
	Level time: 8294515 game time, 9995889 day time
	Level dimension: 0
	Level storage version: 0x04ABD - Anvil
	Level weather: Rain time: 3625 (now: false), thunder time: 106048 (now: false)
	Level game mode: Game mode: survival (ID 0). Hardcore: false. Cheats: false
Stacktrace:
	at net.minecraft.server.MinecraftServer.t(SourceFile:470)
	at net.minecraft.server.MinecraftServer.s(SourceFile:405)
	at bkw.s(SourceFile:124)
	at net.minecraft.server.MinecraftServer.run(SourceFile:339)
	at hh.run(SourceFile:582)

-- System Details --
Details:
	Minecraft Version: 1.6.2
	Operating System: Windows 7 (amd64) version 6.1
	Java Version: 1.6.0_31, Sun Microsystems Inc.
	Java VM Version: Java HotSpot(TM) 64-Bit Server VM (mixed mode), Sun Microsystems Inc.
	Memory: 61245224 bytes (58 MB) / 292159488 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: 6697 (375032 bytes; 0 MB) allocated, 6485 (363160 bytes; 0 MB) used
	Suspicious classes: No suspicious classes found.
	IntCache: cache: 0, tcache: 0, allocated: 3, tallocated: 63
	Profiler Position: N/A (disabled)
	Vec3 Pool Size: 1906 (106736 bytes; 0 MB) allocated, 1400 (78400 bytes; 0 MB) used
	Player Count: 1 / 8; [ju['KADavis'/284814, l='Hanks world', x=-1739.50, y=68.00, z=-852.70]]
	Type: Integrated Server (map_client.txt)
	Is Modded: Probably not. Jar signature remains and both client + server brands are untouched.

You can see this full report at http://hopper.minecraft.net/crashes/minecraft/MCX-5790/812846/