Hopper: java.lang.NullPointerException: Invalid Biome id

This is an automatically generated report based from the following crash: http://hopper.minecraft.net/crashes/minecraft/MCX-779242/

Crash:

java.lang.NullPointerException: Invalid Biome id
	at ags.a(SourceFile:82)

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

---- Minecraft Crash Report ----
// On the bright side, I bought you a teddy bear!

Time: 06/12/13 18:04
Description: Invalid Biome id

java.lang.NullPointerException: Invalid Biome id
	at ags.a(SourceFile:82)
	at agq.<init>(SourceFile:26)
	at agp.a(SourceFile:52)
	at agp.b(SourceFile:61)
	at ags.a(SourceFile:61)
	at aoo.a(SourceFile:933)
	at afs.a(SourceFile:116)
	at afs.a(SourceFile:1047)
	at bmm.j(SourceFile:1343)
	at bmm.a(SourceFile:928)
	at bmm.b(SourceFile:816)
	at azi.ah(SourceFile:779)
	at azi.f(SourceFile:703)
	at net.minecraft.client.main.Main.main(SourceFile:152)


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

-- Head --
Stacktrace:
	at ags.a(SourceFile:82)

-- DownfallBlock --
Details:
	biome id: 0
	downfalls[] size: 256
	x: 0
	z: 0
	w: 16
	h: 16
Stacktrace:
	at ags.a(SourceFile:82)
	at agq.<init>(SourceFile:26)
	at agp.a(SourceFile:52)
	at agp.b(SourceFile:61)
	at ags.a(SourceFile:61)
	at aoo.a(SourceFile:933)

-- Coordinates of biome request --
Details:
	Location: World: (8,0,8), Chunk: (at 8,0,8 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)
Stacktrace:
	at afs.a(SourceFile:116)
	at afs.a(SourceFile:1047)
	at bmm.j(SourceFile:1343)
	at bmm.a(SourceFile:928)

-- Affected level --
Details:
	Level name: MpServer
	All players: 1 total; [bkf['Politeod'/20611, l='MpServer', x=8.50, y=66.62, z=8.50]]
	Chunk stats: MultiplayerChunkCache: 0, 0
	Level seed: 0
	Level generator: ID 00 - default, ver 1. Features enabled: false
	Level generator options: 
	Level spawn location: World: (-84,64,192), Chunk: (at 12,4,0 in -6,12; contains blocks -96,0,192 to -81,255,207), Region: (-1,0; contains chunks -32,0 to -1,31, blocks -512,0,0 to -1,255,511)
	Level time: 0 game time, 0 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: survival (ID 0). Hardcore: false. Cheats: false
	Forced entities: 1 total; [bkf['Politeod'/20611, l='MpServer', x=8.50, y=66.62, z=8.50]]
	Retry entities: 0 total; []
	Server brand: vanilla
	Server type: Integrated singleplayer server
Stacktrace:
	at bka.a(SourceFile:289)
	at azi.b(SourceFile:1944)
	at azi.f(SourceFile:712)
	at net.minecraft.client.main.Main.main(SourceFile:152)

-- System Details --
Details:
	Minecraft Version: 1.7.3
	Operating System: Windows 7 (x86) version 6.1
	Java Version: 1.7.0_45, Oracle Corporation
	Java VM Version: Java HotSpot(TM) Client VM (mixed mode, sharing), Oracle Corporation
	Memory: 122769936 bytes (117 MB) / 518979584 bytes (494 MB) up to 518979584 bytes (494 MB)
	JVM Flags: 2 total; -XX:HeapDumpPath=MojangTricksIntelDriversForPerformance_javaw.exe_minecraft.exe.heapdump -Xmx512M
	AABB Pool Size: 29891 (1673896 bytes; 1 MB) allocated, 17427 (975912 bytes; 0 MB) used
	IntCache: cache: 0, tcache: 17, allocated: 12, tallocated: 94
	Launched Version: 1.7.3
	LWJGL: 2.9.1
	OpenGL: GeForce GTX 560/PCIe/SSE2 GL version 4.3.0, NVIDIA Corporation
	GL Caps: Using GL 1.3 multitexturing.
Using framebuffer objects because OpenGL 3.0 is supported and separate blending is supported.
Anisotropic filtering is supported and maximum anisotropy is 16.
Shaders are available because OpenGL 2.1 is supported.

	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: 16 (896 bytes; 0 MB) allocated, 16 (896 bytes; 0 MB) used
	Anisotropic Filtering: On (16)

You can see this full report at http://hopper.minecraft.net/crashes/minecraft/MCX-779242/36179137/