Error output PLAYER_TELEPORT

Code:

2012-05-06 15:20:31 [WARNING] Can't keep up! Did the system time change, or is the server overloaded?
2012-05-06 15:20:31 [WARNING] Could not properly handle event PLAYER_TELEPORT:
java.lang.IllegalAccessError: Synchronized code got accessed from another thread: java.util.TimerThread
    at org.bukkit.event.Listener.onPlayerTeleport(Listener:0)
    at sun.reflect.GeneratedMethodAccessor185.invoke(Unknown Source)
    at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)
    at java.lang.reflect.Method.invoke(Method.java:616)
    at org.bukkit.plugin.java.JavaPluginLoader$1.execute(JavaPluginLoader.java:301)
    at org.bukkit.plugin.RegisteredListener.callEvent(RegisteredListener.java:62)
    at org.bukkit.plugin.SimplePluginManager.callEvent(SimplePluginManager.java:459)
    at org.bukkit.craftbukkit.entity.CraftPlayer.teleport(CraftPlayer.java:342)
    at org.bukkit.craftbukkit.entity.CraftEntity.teleport(CraftEntity.java:162)
    at uk.co.oliwali.MultiHome.Warmup.run(Warmup.java:42)
    at java.util.TimerThread.mainLoop(Timer.java:534)
    at java.util.TimerThread.run(Timer.java:484)
2012-05-06 15:20:31 [INFO] This error is logged only once: it could have occurred multiple times by now.

Whats my Problem?

 

Do you have 2 plugins that allow players to use /tp or /tpa? If you do I would suggest putting the configuration nodes for each plugin in your permissions.

 

can you me say what is the Plugin