Minecraft crashes when pressing on the "Edit" button when a LAN world is selected (Highlighted)

---- Minecraft Crash Report ----
// My bad.

Time: 7/7/13 4:07 PM
Description: Updating screen events

java.lang.IndexOutOfBoundsException: Index: 3, Size: 3
	at java.util.ArrayList.rangeCheck(Unknown Source)
	at java.util.ArrayList.get(Unknown Source)
	at bdc.a(SourceFile:54)
	at ave.a(SourceFile:169)
	at avv.a(SourceFile:71)
	at avv.d(SourceFile:125)
	at avv.m(SourceFile:109)
	at atn.k(SourceFile:1157)
	at atn.S(SourceFile:662)
	at atn.d(SourceFile:618)
	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 java.util.ArrayList.rangeCheck(Unknown Source)
	at java.util.ArrayList.get(Unknown Source)
	at bdc.a(SourceFile:54)
	at ave.a(SourceFile:169)
	at avv.a(SourceFile:71)
	at avv.d(SourceFile:125)
	at avv.m(SourceFile:109)

-- Affected screen --
Details:
	Screen name: ave
Stacktrace:
	at atn.k(SourceFile:1157)
	at atn.S(SourceFile:662)
	at atn.d(SourceFile:618)
	at net.minecraft.client.main.Main.main(SourceFile:101)

-- System Details --
Details:
	Minecraft Version: 1.6.1
	Operating System: Windows 8 (amd64) version 6.2
	Java Version: 1.7.0_10, Oracle Corporation
	Java VM Version: Java HotSpot(TM) 64-Bit Server VM (mixed mode), Oracle Corporation
	Memory: 140774112 bytes (134 MB) / 191692800 bytes (182 MB) up to 954466304 bytes (910 MB)
	JVM Flags: 1 total; -Xmx1G
	AABB Pool Size: 0 (0 bytes; 0 MB) allocated, 0 (0 bytes; 0 MB) used
	Suspicious classes: No suspicious classes found.
	IntCache: cache: 0, tcache: 0, allocated: 0, tallocated: 0
	Launched Version: 1.6.1
	LWJGL: 2.9.0
	OpenGL: GeForce GT 640/PCIe/SSE2 GL version 4.3.0, NVIDIA Corporation
	Is Modded: Probably not. Jar signature remains and client brand is untouched.
	Type: Client (map_client.txt)
	Resource Pack: Default
	Profiler Position: N/A (disabled)
	Vec3 Pool Size: ~~ERROR~~ NullPointerException: null