So i started a server. I played fine with my friend. and it started giving me stderr problems. had loads of map chunks missing. loads of coven witches spawned and extreme lag came and we couldn't even do anything
How the errors look in the console
2014-07-26 17:07:45 [iNFO] [sTDERR] java.lang.Exception: Stack trace
2014-07-26 17:07:45 [iNFO] [sTDERR] at java.lang.Thread.dumpStack(Unknown So
urce)
2014-07-26 17:07:45 [iNFO] [sTDERR] at net.minecraft.world.chunk.Chunk.func_
76612_a(Chunk.java:908)
2014-07-26 17:07:45 [iNFO] [sTDERR] at net.minecraft.world.World.func_72866_
a(World.java:2395)
2014-07-26 17:07:45 [iNFO] [sTDERR] at net.minecraft.world.WorldServer.func_
72866_a(WorldServer.java:719)
2014-07-26 17:07:45 [iNFO] [sTDERR] at net.minecraft.world.World.func_72870_
g(World.java:2311)
2014-07-26 17:07:45 [iNFO] [sTDERR] at net.minecraft.world.World.func_72939_
s(World.java:2157)
2014-07-26 17:07:45 [iNFO] [sTDERR] at net.minecraft.world.WorldServer.func_
72939_s(WorldServer.java:550)
2014-07-26 17:07:45 [iNFO] [sTDERR] at net.minecraft.server.MinecraftServer.
func_71190_q(MinecraftServer.java:668)
2014-07-26 17:07:45 [iNFO] [sTDERR] at net.minecraft.server.dedicated.Dedica
tedServer.func_71190_q(DedicatedServer.java:276)
2014-07-26 17:07:45 [iNFO] [sTDERR] at net.minecraft.server.MinecraftServer.
func_71217_p(MinecraftServer.java:587)
2014-07-26 17:07:45 [iNFO] [sTDERR] at net.minecraft.server.MinecraftServer.
run(MinecraftServer.java:484)
2014-07-26 17:07:45 [iNFO] [sTDERR] at net.minecraft.server.ThreadMinecraftS
erver.run(SourceFile:583)
2014-07-26 17:07:45 [sEVERE] [Minecraft-Server] Wrong location! EntityItem['item
.tile.bop.stoneFormations.stalactite'/2600, l='world', x=276.61, y=10.13, z=513.
62]
2014-07-26 17:07:45 [iNFO] [sTDERR] java.lang.Exception: Stack trace
2014-07-26 17:07:45 [iNFO] [sTDERR] at java.lang.Thread.dumpStack(Unknown So
urce)
2014-07-26 17:07:45 [iNFO] [sTDERR] at net.minecraft.world.chunk.Chunk.func_
76612_a(Chunk.java:908)
2014-07-26 17:07:45 [iNFO] [sTDERR] at net.minecraft.world.World.func_72866_
a(World.java:2395)
2014-07-26 17:07:45 [iNFO] [sTDERR] at net.minecraft.world.WorldServer.func_
72866_a(WorldServer.java:719)
2014-07-26 17:07:45 [iNFO] [sTDERR] at net.minecraft.world.World.func_72870_
g(World.java:2311)
2014-07-26 17:07:45 [iNFO] [sTDERR] at net.minecraft.world.World.func_72939_
s(World.java:2157)
2014-07-26 17:07:45 [iNFO] [sTDERR] at net.minecraft.world.WorldServer.func_
72939_s(WorldServer.java:550)
2014-07-26 17:07:45 [iNFO] [sTDERR] at net.minecraft.server.MinecraftServer.
func_71190_q(MinecraftServer.java:668)
2014-07-26 17:07:45 [iNFO] [sTDERR] at net.minecraft.server.dedicated.Dedica
tedServer.func_71190_q(DedicatedServer.java:276)
2014-07-26 17:07:45 [iNFO] [sTDERR] at net.minecraft.server.MinecraftServer.
func_71217_p(MinecraftServer.java:587)
2014-07-26 17:07:45 [iNFO] [sTDERR] at net.minecraft.server.MinecraftServer.
run(MinecraftServer.java:484)
2014-07-26 17:07:45 [iNFO] [sTDERR] at net.minecraft.server.ThreadMinecraftS
erver.run(SourceFile:583)