This is also helpful: http://ubuntuforums.org/showthread.php?t=1477297
Because I prefer using Thunderbird mail client instead of Evolution mail client, I tried other mail notification instead of default mail notification which only support Evolution mail client. After trying different mail notification, I decide to use gnome gmail notifier(Gmail Notifier). gm-notify can be integrated into gnome indicator applet well, but it doesn't support multi-accounts. Gnome gmail notifier can't be integrated into gnome indicator applet. Although gnome indicator applet support many chat accounts and message accounts which are included in Empathy IM client. But I only use Skype which is not included in Empathy IM client. So I will remove the panel of gnome indicator applet and MeMenu(This is also about status of those chat services.)
sudo apt-get remove evolution-indicator evolution
messaging notifications:
sudo apt-get remove indicator-messages
MeMenu:
sudo apt-get remove indicator-me
refresh the gnome panel:
killall gnome-panel
