error handling client message [C] 48 ValidatePositionjava.lang.NullPointerException at java.util.TreeMap.rotateRight(Unknown Source) at java.util.TreeMap.fixAfterInsertion(Unknown Source) at java.util.TreeMap.put(Unknown Source) at java.util.TreeSet.add(Unknown Source) at net.sf.l2j.gameserver.Universe.registerHeight(Universe.java:340) at net.sf.l2j.gameserver.clientpackets.ValidatePosition.runImpl(ValidatePosition.java:80) 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)