Add system tray notifications to QT application under MAC

I have a QT 4.8 cross platform application which is already perfectly running. The problem is that it shows notifications (QSystemTrayIcon::showMessage()) only on Windows and Linux, while nothing is show on Mac. I need someone expert on QT developement under MAC, to add system notifications when running under MAC. Maybe we need to integrate to Growl or at least to use Growl SDK to show these messages. I prefeer someone who already did this, so he knows how to do an can complete the project quickly. It is enough for me to get full source code of an example application, which is showing system notification popups, so that I can integrate myself on my application. Or I can provude my sources to be modified. Thank you