error handling client message [C] 48 ValidatePosition
java.lang.NullPointerException
        at javolution.util.FastCollection$FastIterator.next(FastCollection.java:547)
        at net.sf.l2j.gameserver.util.CharacterKnownList.forgetDistantObjects(CharacterKnownList.java:103)
        at net.sf.l2j.gameserver.util.CharacterKnownList.forgetDistantObjects(CharacterKnownList.java:85)
        at net.sf.l2j.gameserver.util.CharacterKnownList.updateKnownObjects(CharacterKnownList.java:77)
        at net.sf.l2j.gameserver.model.L2Character.updateKnownObjects(L2Character.java:3202)
        at net.sf.l2j.gameserver.clientpackets.ValidatePosition.runImpl(ValidatePosition.java:110)
        at net.sf.l2j.gameserver.clientpackets.ClientBasePacket.run(ClientBasePacket.java:56)
        at java.util.concurrent.Executors$RunnableAdapter.call(Unknown Source)
        at java.util.concurrent.FutureTask$Sync.innerRun(Unknown Source)
        at java.util.concurrent.FutureTask.run(Unknown Source)
        at java.util.concurrent.ScheduledThreadPoolExecutor$ScheduledFutureTask.access$301(Unknown Source)
        at java.util.concurrent.ScheduledThreadPoolExecutor$ScheduledFutureTask.run(Unknown Source)
        at java.util.concurrent.ThreadPoolExecutor$Worker.runTask(Unknown Source)
        at java.util.concurrent.ThreadPoolExecutor$Worker.run(Unknown Source)
        at java.lang.Thread.run(Unknown Source)