>>This has to be done manually. I can't decide for you if you want to get rid of the actual new messages map by overwritting it which will simulate a new login. This operation has to be done manually. It's a decision of the user to decide when he want to click refresh which will simulate a new login.
If I do that. The refresh might occur on the map panel and the user might not even know that some messages were added. Also, when he'll click refresh or login again, he will have those messages back because they were created after he entered.