private void enterRoom(ServerClient activeclient, Msg nextCMD)
	{
		Room leaving = new Room("null");
		for (Room r : rooms)
		{
			if (r.getClientsInRoom().contains(activeclient)) // which room shell be left ?
			{
				leaving = r;
			}
			if (r.getName().equals(nextCMD.getContent())) // which room shell be entered ?
			{
				r.addClientToRoom(activeclient); // enter
			}
		}
		leaving.rmClientFromRoom(activeclient); // leave needs to be before all get to know, because this client is already registered with its new entry at its new room.
		for (Room r : rooms)
		{
			r.roomBroadcast(activeclient, new Msg("moved|"+leaving.getName()+"|"+nextCMD.getContent(), activeclient.getNickname(), 'i', r.getName())); // everyone needs to know what is going on
		}
	}