---- Minecraft Crash Report ----
// I just don't know what went wrong

Time: 21/06/14 14:05
Description: Exception while updating neighbours

java.lang.ArrayIndexOutOfBoundsException: 6
at apo.h(SourceFile:381)
at apo.e(SourceFile:142)
at apo.a(SourceFile:120)
at aha.e(SourceFile:479)
at aha.d(SourceFile:457)
at aha.c(SourceFile:427)
at aha.d(SourceFile:336)
at abg.a(SourceFile:68)
at adc.a(SourceFile:107)
at mw.a(SourceFile:248)
at ng.a(SourceFile:366)
at jo.a(SourceFile:60)
at jo.a(SourceFile:9)
at ej.a(SourceFile:174)
at nb.c(SourceFile:134)
at net.minecraft.server.MinecraftServer.v(SourceFile:540)
at net.minecraft.server.MinecraftServer.u(SourceFile:453)
at bvj.u(IntegratedServer.java:186)
at net.minecraft.server.MinecraftServer.run(SourceFile:369)
at li.run(SourceFile:628)

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

– Head –
Stacktrace:
at apo.h(SourceFile:381)
at apo.e(SourceFile:142)
at apo.a(SourceFile:120)

– Block being updated –
Details:
Source block type: ID #0 (tile.air // aiz)
Block type: ID #29 (tile.pistonStickyBase // apo)
Block data value: 6 / 0x6 / 0b0110
Block location: World: (-253,65,236), Chunk: (at 3,4,12 in -16,14; contains blocks -256,0,224 to -241,255,239), Region: (-1,0; contains chunks -32,0 to -1,31, blocks -512,0,0 to -1,255,511)
Stacktrace:
at aha.e(SourceFile:479)
at aha.d(SourceFile:457)
at aha.c(SourceFile:427)
at aha.d(SourceFile:336)
at abg.a(SourceFile:68)
at adc.a(SourceFile:107)
at mw.a(SourceFile:248)
at ng.a(SourceFile:366)
at jo.a(SourceFile:60)
at jo.a(SourceFile:9)
at ej.a(SourceFile:174)

– Ticking connection –
Details:
Connection: ej@33e9eef5
Stacktrace:
at nb.c(SourceFile:134)
at net.minecraft.server.MinecraftServer.v(SourceFile:540)
at net.minecraft.server.MinecraftServer.u(SourceFile:453)
at bvj.u(IntegratedServer.java:186)
at net.minecraft.server.MinecraftServer.run(SourceFile:369)
at li.run(SourceFile:628)

– System Details –
Details:
Minecraft Version: 1.7.9
Operating System: Windows 7 (amd64) version 6.1
Java Version: 1.7.0_51, Oracle Corporation
Java VM Version: Java HotSpot(TM) 64-Bit Server VM (mixed mode), Oracle Corporation
Memory: 120012888 bytes (114 MB) / 467664896 bytes (446 MB) up to 954728448 bytes (910 MB)
JVM Flags: 2 total; -XX:HeapDumpPath=MojangTricksIntelDriversForPerformance_javaw.exe_minecraft.exe.heapdump -Xmx1G
AABB Pool Size: 0 (0 bytes; 0 MB) allocated, 0 (0 bytes; 0 MB) used
IntCache: cache: 0, tcache: 0, allocated: 12, tallocated: 94
Profiler Position: N/A (disabled)
Vec3 Pool Size: 0 (0 bytes; 0 MB) allocated, 0 (0 bytes; 0 MB) used
Player Count: 1 / 8; [mv['ArrranWeeviling'/271, l='test1', x=-249.98, y=66.21, z=236.19]]
Type: Integrated Server (map_client.txt)
Is Modded: Very likely; Jar signature invalidated

My Minecraft isn't modded