// following errors occur: (first two are most frequent)
error handling client message [C] 01 MoveBackwardToLoc
error handling client message [C] 48 ValidatePosition
deletedMe()
// all produce same message: 
java.lang.IllegalStateException
        at net.sf.l2j.util.L2ObjectHashSet.remove(L2ObjectHashSet.java:208)
        at net.sf.l2j.gameserver.model.L2WorldRegion.removeVisibleObject(L2WorldRegion.java:82)
        at net.sf.l2j.gameserver.model.L2Object.updateCurrentWorldRegion(L2Object.java:444)
        at net.sf.l2j.gameserver.model.L2Object.setXYZ(L2Object.java:151)
        at net.sf.l2j.gameserver.clientpackets.MoveBackwardToLocation.runImpl(MoveBackwardToLocation.java:96)
        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)
// I'm using rev 434 I don't believe any of those files have been changed since then so u can just take a look at latest rev