Persistent desktop notification?

Do we have a persistant desktop notification API? Which stick till user dimisses it?

nsIAlertSerivice notifications only last 4 seconds. If i fake persistance with this, i listen to callback on close, and if it wasnt closed due to user click then i re-post that notification which is annoying as its confusing, as the fade out and fade in a of new notif happens and worst of all position can change if multiple notifs are present.

There is notification box Alerts and Notifications

Thanks man Im using these and love them, but I needed to show a notification when use is not focused in the browser, and maybe not at the computer at the time.