code: @Override
  	int getOldID() {
  		int ID_ = getID();
  
  		if (m_userOldestWkid != -1)
  			return m_userOldestWkid;
  
  		m_userOldestWkid = Wkid.wkid_to_old(ID_);
  
  		if (m_userOldestWkid != -1)
  			return m_userOldestWkid;
  
  		return ID_;
  	}
docs: Returns the oldest value of the well known ID for the horizontal
  coordinate system of the spatial reference. This ID is used for JSON
  serialization. Not public.