Entity Error

*This Error Crashed my Server:*

---- Minecraft Crash Report ----
// Everything's going to plan. No, really, that was supposed to happen.

Time: 19.01.13 12:01
Description: Ticking entity

java.lang.ArrayIndexOutOfBoundsException: -1
	at aar.a(SourceFile:314)
	at aar.e(SourceFile:535)
	at yv.r(SourceFile:1579)
	at apa.b(SourceFile:290)
	at apa.b(SourceFile:270)
	at apa.a(SourceFile:168)
	at qn.aB(SourceFile:97)
	at qn.l_(SourceFile:90)
	at yv.a(SourceFile:1312)
	at iq.a(SourceFile:480)
	at yv.g(SourceFile:1290)
	at yv.h(SourceFile:1197)
	at iq.h(SourceFile:374)
	at net.minecraft.server.MinecraftServer.r(SourceFile:460)
	at hq.r(SourceFile:248)
	at net.minecraft.server.MinecraftServer.q(SourceFile:395)
	at net.minecraft.server.MinecraftServer.run(SourceFile:329)
	at gi.run(SourceFile:565)


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

-- Head --
Stacktrace:
	at aar.a(SourceFile:314)
	at aar.e(SourceFile:535)
	at yv.r(SourceFile:1579)
	at apa.b(SourceFile:290)
	at apa.b(SourceFile:270)
	at apa.a(SourceFile:168)
	at qn.aB(SourceFile:97)
	at qn.l_(SourceFile:90)
	at yv.a(SourceFile:1312)
	at iq.a(SourceFile:480)
	at yv.g(SourceFile:1290)

-- Entity being ticked --
Details:
	*Entity Type: MinecartHopper (qn)*
	Entity ID: 31
	*Entity Name: entity.MinecartHopper.name*
	Entity's Exact location: -1817.92, -1.09, -1256.48
	Entity's Block location: World: (-1818,-2,-1257), Chunk: (at 6,-1,7 in -114,-79; contains blocks -1824,0,-1264 to -1809,255,-1249), Region: (-4,-3; contains chunks -128,-96 to -97,-65, blocks -2048,0,-1536 to -1537,255,-1025)
	Entity's Momentum: -0.00, 0.00, 0.00
Stacktrace:
	at yv.h(SourceFile:1197)
	at iq.h(SourceFile:374)

-- Affected level --
Details:
	Level name: 13w03a
	All players: 1 total; [it['Wombosvideo'/32, l='13w03a', x=-1818.44, y=56.25, z=-1262.48]]
	Chunk stats: ServerChunkCache: 901 Drop: 0
	Level seed: 1683384460373016645
	Level generator: ID 01 - flat, ver 0. Features enabled: false
	Level generator options: 2;7,3x1,52x24;2;
	Level spawn location: World: (-2013,4,-1392), Chunk: (at 3,0,0 in -126,-87; contains blocks -2016,0,-1392 to -2001,255,-1377), Region: (-4,-3; contains chunks -128,-96 to -97,-65, blocks -2048,0,-1536 to -1537,255,-1025)
	Level time: 169104 game time, 149336 day time
	Level dimension: 0
	Level storage version: 0x04ABD - Anvil
	Level weather: Rain time: 13287 (now: true), thunder time: 4696 (now: false)
	Level game mode: Game mode: creative (ID 1). Hardcore: false. Cheats: true
Stacktrace:
	at net.minecraft.server.MinecraftServer.r(SourceFile:460)
	at hq.r(SourceFile:248)
	at net.minecraft.server.MinecraftServer.q(SourceFile:395)
	at net.minecraft.server.MinecraftServer.run(SourceFile:329)
	at gi.run(SourceFile:565)

-- System Details --
Details:
	Minecraft Version: 13w03a
	Operating System: Windows 7 (amd64) version 6.1
	Java Version: 1.7.0_11, Oracle Corporation
	Java VM Version: Java HotSpot(TM) 64-Bit Server VM (mixed mode), Oracle Corporation
	Memory: 249552152 bytes (237 MB) / 416940032 bytes (397 MB) up to 1897725952 bytes (1809 MB)
	JVM Flags: 0 total; 
	AABB Pool Size: 1035 (57960 bytes; 0 MB) allocated, 209 (11704 bytes; 0 MB) used
	Suspicious classes: No suspicious classes found.
	IntCache: cache: 0, tcache: 0, allocated: 0, tallocated: 0
	Profiler Position: N/A (disabled)
	Vec3 Pool Size: 3084 (172704 bytes; 0 MB) allocated, 29 (1624 bytes; 0 MB) used
	Player Count: 1 / 20; [it['Wombosvideo'/32, l='13w03a', x=-1818.44, y=56.25, z=-1262.48]]
	Is Modded: Unknown (can't tell)
	Type: Dedicated Server (map_server.txt)