2011-02-17 11:10:28 [SEVERE] Unexpected exception
java.lang.ArrayIndexOutOfBoundsException: -1
    at net.minecraft.server.ChunkCache.getTypeId(SourceFile:38)
    at net.minecraft.server.ChunkCache.getMaterial(SourceFile:103)
    at net.minecraft.server.Pathfinder.a(SourceFile:158)
    at net.minecraft.server.Pathfinder.a(SourceFile:120)
    at net.minecraft.server.Pathfinder.b(SourceFile:96)
    at net.minecraft.server.Pathfinder.a(SourceFile:64)
    at net.minecraft.server.Pathfinder.a(SourceFile:37)
    at net.minecraft.server.Pathfinder.a(SourceFile:22)
    at net.minecraft.server.World.a(World.java:1682)
    at net.minecraft.server.EntityCreature.d(EntityCreature.java:45)
    at net.minecraft.server.EntityLiving.o(EntityLiving.java:641)
    at net.minecraft.server.EntityMonster.o(EntityMonster.java:30)
    at net.minecraft.server.EntityLiving.b_(EntityLiving.java:226)
    at net.minecraft.server.EntityMonster.b_(EntityMonster.java:34)
    at net.minecraft.server.World.a(World.java:1059)
    at net.minecraft.server.WorldServer.a(WorldServer.java:57)
    at net.minecraft.server.World.f(World.java:1041)
    at net.minecraft.server.World.c(World.java:1018)
    at net.minecraft.server.MinecraftServer.h(MinecraftServer.java:313)
    at net.minecraft.server.MinecraftServer.run(MinecraftServer.java:232)
    at net.minecraft.server.ThreadServerApplication.run(SourceFile:512)