xAuth Error

2011-12-29 01:35:06 [SEVERE] java.lang.IllegalAccessError: Synchronized code got accessed from another thread: com.cypherx.xauth.xAuth$1
2011-12-29 01:35:06 [SEVERE]    at org.bukkit.event.player.PlayerListener.onPlayerKick(PlayerListener:0)
2011-12-29 01:35:06 [SEVERE]    at org.bukkit.plugin.java.JavaPluginLoader$4.execute(JavaPluginLoader.java:286)
2011-12-29 01:35:06 [SEVERE]    at org.bukkit.plugin.RegisteredListener.callEvent(RegisteredListener.java:58)
2011-12-29 01:35:06 [SEVERE]    at org.bukkit.plugin.SimplePluginManager.callEvent(SimplePluginManager.java:339)
2011-12-29 01:35:06 [SEVERE]    at net.minecraft.server.NetServerHandler.disconnect(NetServerHandler.java:107)
2011-12-29 01:35:06 [SEVERE]    at org.getspout.spout.SpoutNetServerHandler.disconnect(SpoutNetServerHandler.java:560)
2011-12-29 01:35:06 [SEVERE]    at org.bukkit.craftbukkit.entity.CraftPlayer.kickPlayer(CraftPlayer.java:185)
2011-12-29 01:35:06 [SEVERE]    at com.cypherx.xauth.xAuth$1.run(xAuth.java:263)
2011-12-29 01:35:06 [SEVERE]    at org.bukkit.craftbukkit.scheduler.CraftWorker.run(CraftWorker.java:34)
2011-12-29 01:35:06 [SEVERE] java.lang.IllegalAccessError: Synchronized code got accessed from another thread: com.cypherx.xauth.xAuth$1
2011-12-29 01:35:06 [SEVERE]    at com.bergerkiller.bukkit.nolagg.ChunkSendQueue.remove(ChunkSendQueue.java:345)
2011-12-29 01:35:06 [SEVERE]    at net.minecraft.server.PlayerInstance.b(PlayerInstance.java:63)
2011-12-29 01:35:06 [SEVERE]    at net.minecraft.server.PlayerManager.removePlayer(PlayerManager.java:109)
2011-12-29 01:35:06 [SEVERE]    at net.minecraft.server.ServerConfigurationManager.disconnect(ServerConfigurationManager.java:159)
2011-12-29 01:35:06 [SEVERE]    at net.minecraft.server.NetServerHandler.disconnect(NetServerHandler.java:128)
2011-12-29 01:35:06 [SEVERE]    at org.getspout.spout.SpoutNetServerHandler.disconnect(SpoutNetServerHandler.java:560)
2011-12-29 01:35:06 [SEVERE]    at org.bukkit.craftbukkit.entity.CraftPlayer.kickPlayer(CraftPlayer.java:185)
2011-12-29 01:35:06 [SEVERE]    at com.cypherx.xauth.xAuth$1.run(xAuth.java:263)
2011-12-29 01:35:06 [SEVERE]    at org.bukkit.craftbukkit.scheduler.CraftWorker.run(CraftWorker.java:34)
2011-12-29 01:35:06 [SEVERE] java.lang.IllegalAccessError: Synchronized code got accessed from another thread: com.cypherx.xauth.xAuth$1
2011-12-29 01:35:06 [SEVERE]    at org.bukkit.event.player.PlayerListener.onPlayerQuit(PlayerListener:0)
2011-12-29 01:35:06 [SEVERE]    at org.bukkit.plugin.java.JavaPluginLoader$2.execute(JavaPluginLoader.java:272)
2011-12-29 01:35:06 [SEVERE]    at org.bukkit.plugin.RegisteredListener.callEvent(RegisteredListener.java:58)
2011-12-29 01:35:06 [SEVERE]    at org.bukkit.plugin.SimplePluginManager.callEvent(SimplePluginManager.java:339)
2011-12-29 01:35:06 [SEVERE]    at net.minecraft.server.ServerConfigurationManager.disconnect(ServerConfigurationManager.java:161)
2011-12-29 01:35:06 [SEVERE]    at net.minecraft.server.NetServerHandler.disconnect(NetServerHandler.java:128)
2011-12-29 01:35:06 [SEVERE]    at org.getspout.spout.SpoutNetServerHandler.disconnect(SpoutNetServerHandler.java:560)
2011-12-29 01:35:06 [SEVERE]    at org.bukkit.craftbukkit.entity.CraftPlayer.kickPlayer(CraftPlayer.java:185)
2011-12-29 01:35:06 [SEVERE]    at com.cypherx.xauth.xAuth$1.run(xAuth.java:263)
2011-12-29 01:35:06 [SEVERE]    at org.bukkit.craftbukkit.scheduler.CraftWorker.run(CraftWorker.java:34)