Error

I got this error report trying to log into my favorite server today:

---- Minecraft Crash Report ----
// Would you like a cupcake?

Time: 03/12/12 8:13 PM
Description: Unexpected error

java.lang.NullPointerException
at bap.a(SourceFile:197)
at bap.b(SourceFile:397)
at net.minecraft.client.Minecraft.run(SourceFile:530)
at java.lang.Thread.run(Unknown Source)


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

-- Affected level --
Details:
Level name: MpServer
All players: 3 total; [ayk['assassinsknife'/135549, l='MpServer', x=-561.30, y=65.62, z=-3490.62], azw['Krayolla'/12604, l='MpServer', x=-596.66, y=64.00, z=-3534.64], azw['ssgoku411'/3413, l='MpServer', x=-603.56, y=64.00, z=-3531.78]]
Chunk stats: MultiplayerChunkCache: 25
Level seed: 0
Level generator: ID 00 - default, ver 1. Features enabled: false
Level generator options:
Level spawn location: World: (-647,68,-3526), Chunk: (at 9,4,10 in -41,-221; contains blocks -656,0,-3536 to -641,255,-3521), Region: (-2,-7; contains chunks -64,-224 to -33,-193, blocks -1024,0,-3584 to -513,255,-3073)
Level time: 239116584 game time, 239232132 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: 23 total; [ayk['assassinsknife'/135549, l='MpServer', x=-561.30, y=65.62, z=-3490.62], mg['Painting'/3097, l='MpServer', x=-602.50, y=34.50, z=-3477.94], mc['entity.ItemFrame.name'/3096, l='MpServer', x=-601.06, y=9.50, z=-3511.50], mg['Painting'/3099, l='MpServer', x=-607.00, y=35.00, z=-3472.06], mg['Painting'/3098, l='MpServer', x=-602.50, y=34.50, z=-3472.06], mg['Painting'/3101, l='MpServer', x=-593.50, y=65.50, z=-3467.94], mg['Painting'/3101, l='MpServer', x=-593.50, y=65.50, z=-3467.94], mg['Painting'/3100, l='MpServer', x=-592.06, y=65.00, z=-3468.50], qn['Skeleton'/49034, l='MpServer', x=-597.94, y=47.00, z=-3522.47], mc['entity.ItemFrame.name'/3103, l='MpServer', x=-589.94, y=64.50, z=-3516.50], mg['Painting'/3100, l='MpServer', x=-592.06, y=65.00, z=-3468.50], pc['entity.Cat.name'/3102, l='MpServer', x=-588.94, y=64.00, z=-3530.69], qc['Creeper'/118999, l='MpServer', x=-591.50, y=20.00, z=-3501.50], mg['Painting'/3097, l='MpServer', x=-602.50, y=34.50, z=-3477.94], qr['Zombie'/123683, l='MpServer', x=-586.50, y=60.00, z=-3496.50], mg['Painting'/3099, l='MpServer', x=-607.00, y=35.00, z=-3472.06], mg['Painting'/3098, l='MpServer', x=-602.50, y=34.50, z=-3472.06], azw['Krayolla'/12604, l='MpServer', x=-596.66, y=64.00, z=-3534.64], azw['ssgoku411'/3413, l='MpServer', x=-603.56, y=64.00, z=-3531.78], azw['Krayolla'/12604, l='MpServer', x=-596.66, y=64.00, z=-3534.64], mc['entity.ItemFrame.name'/3095, l='MpServer', x=-601.06, y=9.50, z=-3506.50], azw['ssgoku411'/3413, l='MpServer', x=-603.56, y=64.00, z=-3531.78], mc['entity.ItemFrame.name'/3104, l='MpServer', x=-589.94, y=64.50, z=-3511.50]]
Retry entities: 0 total; []
Stacktrace:
at ayh.a(SourceFile:290)
at net.minecraft.client.Minecraft.b(SourceFile:1870)
at net.minecraft.client.Minecraft.run(SourceFile:548)
at java.lang.Thread.run(Unknown Source)

-- System Details --
Details:
Minecraft Version: 1.4.5
Operating System: Windows 7 (amd64) version 6.1
Java Version: 1.6.0_22, Sun Microsystems Inc.
Java VM Version: Java HotSpot(TM) 64-Bit Server VM (mixed mode), Sun Microsystems Inc.
Memory: 447968232 bytes (427 MB) / 514523136 bytes (490 MB) up to 954466304 bytes (910 MB)
JVM Flags: 2 total; -Xms512m -Xmx1024m
AABB Pool Size: 22127 (1239112 bytes; 1 MB) allocated, 22127 (1239112 bytes; 1 MB) used
Suspicious classes: No suspicious classes found.
IntCache: cache: 0, tcache: 0, allocated: 0, tallocated: 0
LWJGL: 2.4.2
OpenGL: AMD Radeon HD 6310 Graphics GL version 4.1.10429 Compatibility Profile Context, ATI Technologies Inc.
Is Modded: Probably not. Jar signature remains and client brand is untouched.
Type: Client (map_client.txt)
Texture Pack: Default
Profiler Position: N/A (disabled)
Vec3 Pool Size: 42 (2352 bytes; 0 MB) allocated, 42 (2352 bytes; 0 MB) used