Problem/Bug AutoSaveWorld don't work

Hello. I have bug with plugin AutoSaveWorld on my server.

If I stopping it, server is shutdown with error:

Code:

>stop
[15:28:06 INFO]: CONSOLE: Stopping the server..
[15:28:06 WARN]: java.lang.InterruptedException: sleep interrupted
[15:28:06 WARN]:        at java.lang.Thread.sleep(Native Method)
[15:28:06 WARN]:        at net.minecraft.world.storage.ThreadedFileIOBase.func_75734_a(ThreadedFileIOBase.java:80)
[15:28:06 WARN]:        at net.minecraft.world.chunk.storage.AnvilSaveHandler.func_75759_a(AnvilSaveHandler.java:55)
[15:28:06 WARN]:        at net.minecraft.world.WorldServer.func_73041_k(WorldServer.java:1242)
[1 saw5:28:06 WARN]:        at net.minecraft.server.MinecraftServer.func_71267_a(MinecraftServer.java:532)
[15:28:06 WARN]:        at kcauldron.KCauldronWorldSaveThread.run(KCauldronWorldSaveThread.java:39)

What I doing wrong?