multi-level menu with Ajax support ?

multi-level menu with Ajax support ?

I am looking for a multi-level menu, like JQuery Superfish plugin, has ajax support. When page is loaded, top level menu item will be loaded, then click this top-level menu item, it will use ajax to get JSon data from server, and add new item as its lower-level menu item.

Looks like Superfish doesn't support Ajax. Do you have any recommendation ?

Thanks.