"[13:27:52] [Server thread/ERROR]: "Silently" catching entity tracking error.
net.minecraft.util.ReportedException: Adding entity to track
        at net.minecraft.entity.EntityTracker.func_72785_a(EntityTracker.java:23
0) [mn.class:?]
        at cpw.mods.fml.common.registry.EntityRegistry.tryTrackingEntity(EntityR
egistry.java:364) [EntityRegistry.class:?]
        at net.minecraft.entity.EntityTracker.func_72786_a(EntityTracker.java:61
) [mn.class:?]
        at net.minecraft.world.WorldManager.func_72703_a(SourceFile:31) [mp.clas
s:?]
        at net.minecraft.world.World.func_72923_a(World.java:1347) [ahb.class:?]

        at net.minecraft.world.WorldServer.func_72923_a(WorldServer.java:844) [m
t.class:?]
        at net.minecraft.world.World.func_72868_a(World.java:3304) [ahb.class:?]

        at net.minecraft.world.chunk.Chunk.func_76631_c(Chunk.java:921) [apx.cla
ss:?]
        at net.minecraftforge.common.chunkio.ChunkIOProvider.callStage2(ChunkIOP
rovider.java:46) [ChunkIOProvider.class:?]
        at net.minecraftforge.common.chunkio.ChunkIOProvider.callStage2(ChunkIOP
rovider.java:12) [ChunkIOProvider.class:?]
        at net.minecraftforge.common.util.AsynchronousExecutor.skipQueue(Asynchr
onousExecutor.java:344) [AsynchronousExecutor.class:?]
        at net.minecraftforge.common.util.AsynchronousExecutor.getSkipQueue(Asyn
chronousExecutor.java:302) [AsynchronousExecutor.class:?]
        at net.minecraftforge.common.chunkio.ChunkIOExecutor.syncChunkLoad(Chunk
IOExecutor.java:12) [ChunkIOExecutor.class:?]
        at net.minecraft.world.gen.ChunkProviderServer.loadChunk(ChunkProviderSe
rver.java:126) [ms.class:?]
        at net.minecraft.world.gen.ChunkProviderServer.func_73158_c(ChunkProvide
rServer.java:101) [ms.class:?]
        at net.minecraft.world.gen.ChunkProviderServer.func_73154_d(ChunkProvide
rServer.java:199) [ms.class:?]
        at net.minecraft.world.World.func_72964_e(World.java:419) [ahb.class:?]
        at net.minecraft.world.World.func_147439_a(World.java:345) [ahb.class:?]

        at net.minecraft.block.BlockStaticLiquid.func_149817_o(SourceFile:64) [a
nt.class:?]
        at net.minecraft.block.BlockStaticLiquid.func_149674_a(SourceFile:41) [a
nt.class:?]
        at net.minecraft.world.WorldServer.func_147456_g(WorldServer.java:391) [
mt.class:?]
        at net.minecraft.world.WorldServer.func_72835_b(WorldServer.java:183) [m
t.class:?]
        at net.minecraft.server.MinecraftServer.func_71190_q(MinecraftServer.jav
a:625) [MinecraftServer.class:?]
        at net.minecraft.server.dedicated.DedicatedServer.func_71190_q(Dedicated
Server.java:334) [lt.class:?]
        at net.minecraft.server.MinecraftServer.func_71217_p(MinecraftServer.jav
a:547) [MinecraftServer.class:?]
        at net.minecraft.server.MinecraftServer.run(MinecraftServer.java:427) [M
inecraftServer.class:?]
        at net.minecraft.server.MinecraftServer$2.run(MinecraftServer.java:685)
[li.class:?]
Caused by: java.lang.IllegalStateException: Entity is already tracked!
        at net.minecraft.entity.EntityTracker.func_72785_a(EntityTracker.java:19
6) ~[mn.class:?]
        ... 26 more"