NPE with abstract rooms

[ebullient]

[10/14/16 14:42:36:457 UTC] 00000990 id= net.wasdev.gameon.mediator W : 450ce58c : Uncaught exception handling room-bound message
java.lang.NullPointerException: Value in JsonObjects name/value pair cannot be null
at org.glassfish.json.JsonObjectBuilderImpl.validateValue(JsonObjectBuilderImpl.java:164)
at org.glassfish.json.JsonObjectBuilderImpl.add(JsonObjectBuilderImpl.java:74)
at org.gameontext.mediator.room.AbstractRoomMediator.buildLocationResponse(AbstractRoomMediator.java:261)
at org.gameontext.mediator.room.AbstractRoomMediator.getLocationEventMessage(AbstractRoomMediator.java:198)
at org.gameontext.mediator.room.RemoteRoomProxy.getLocationEventMessage(RemoteRoomProxy.java:227)
at org.gameontext.mediator.ClientMediator.setRoomMediator(ClientMediator.java:99)
at org.gameontext.mediator.MediatorNexus$ClientMediatorPod.lambda$join$5(MediatorNexus.java:265)