onmouseout and onmouseleave

onmouseleave is only for IE, but is helpful to suppress the event from the children nodes.

Some introduction in http://www.quirksmode.org/js/events_mouse.html.

Actually, I am looking how to have cascading menu disappear when mouse out.
I hope this example http://bytes.com/forum/thread553630.html is going to help. Got to try it later on.