public void openConversationWindowFor(String username, String name) {
    ConversationPanel panel = conversations.get(username);
    if (panel == null) {
      panel = new ConversationPanel(username);
      panel.registerMessageListener(this);
      if (conversationWindow == null) {
        conversationWindow = new ConversationWindow(name, panel);
        conversationWindow.registerConversationListener(this);
      }
      else {
        conversationWindow.addConversationPanel(name, panel);
      }
      conversations.put(username, panel);
    }
    conversationWindow.setSelectedTab(panel);
  }