some time I am facing following exception on closing client by killing client in metadataAdapter
Exception in thread "TIMER FOR PUMPS PARKING DESTROYER" java.lang.NullPointerException
at com.iontrading.lightstreamer.dataadapter.MixedMeta dataAdapter.notifySessionClose(MixedMetadataAdapte

and i think because of this exception I am not getting unsubscription call at dataAdapter

Please let me know the reason of this exception