Minecraft server proč se to děje?

Proč se to děje, když se připojí jakýkoliv druhý hráč kromne mne?
celý crash: www.dropbox.com

[17:09:52 ERROR]: Encountered an unexpected exception
java.lang.ArrayIndexOutOfBoundsException: -1
at java.util.concurrent.CopyOnWriteArrayList.get(Unkn own Source) ~[?:1.7
.0_55]
at java.util.concurrent.CopyOnWriteArrayList.get(Unkn own Source) ~[?:1.7
.0_55]
at net.minecraft.server.v1_7_R1.PlayerList.tick(Playe rList.java:777) ~[s
pigot.jar:git-Spigot-1308]
at net.minecraft.server.v1_7_R1.MinecraftServer.u(Min ecraftServer.java:7
02) ~[spigot.jar:git-Spigot-1308]
at net.minecraft.server.v1_7_R1.DedicatedServer.u(Ded icatedServer.java:2
73) ~[spigot.jar:git-Spigot-1308]
at net.minecraft.server.v1_7_R1.MinecraftServer.t(Min ecraftServer.java:5
60) ~[spigot.jar:git-Spigot-1308]
at net.minecraft.server.v1_7_R1.MinecraftServer.run(M inecraftServer.java
:467) [spigot.jar:git-Spigot-1308]

...

[17:11:00 ERROR]: ------------------------------
[17:11:00 ERROR]: Current Thread: Netty IO #0
[17:11:00 ERROR]: PID: 22 | Suspended: false | Native: true | State: RUNNA
BLE
[17:11:00 ERROR]: Thread is waiting on monitor(s):
[17:11:00 ERROR]: Locked on:sun.nio.ch.SelectorImpl.lockAndDoSelec
t(Unknown Source)
[17:11:00 ERROR]: Locked on:sun.nio.ch.SelectorImpl.lockAndDoSelec
t(Unknown Source)
[17:11:00 ERROR]: Locked on:sun.nio.ch.SelectorImpl.lockAndDoSelec
t(Unknown Source)
[17:11:00 ERROR]: Stack:
[17:11:00 ERROR]: sun.nio.ch.WindowsSelectorImpl$SubSelector.poll0
(Native Method)
[17:11:00 ERROR]: sun.nio.ch.WindowsSelectorImpl$SubSelector.poll(
Unknown Source)
[17:11:00 ERROR]: sun.nio.ch.WindowsSelectorImpl$SubSelector.acces
s$400(Unknown Source)
[17:11:00 ERROR]: sun.nio.ch.WindowsSelectorImpl.doSelect(Unknown
Source)
[17:11:00 ERROR]: sun.nio.ch.SelectorImpl.lockAndDoSelect(Unknown
Source)
[17:11:00 ERROR]: sun.nio.ch.SelectorImpl.select(Unknown Source)
>Pokračujte stisknutím libovolné klávesy...