There's a couple forum posting about this. Here's the method from DataPaginator.java:

    public void broadcast(FacesEvent event) throws AbortProcessingException {
        super.broadcast(event);

        if (event instanceof PaginatorActionEvent) {
            PaginatorActionEvent scrollerEvent = (PaginatorActionEvent) event;
            broadcastToActionListener(scrollerEvent);
            UIData uiData = getUIData();
            if (uiData == null) {
                return;
            }

            // Now, all the code to actually change the page
        }
    }


Because of this, applications can't act on which page is going to be changed to, since they really only have the current/old page info. Also, it looks like PaginatorActionEvent can have a page index if the user clicked on a specific page, but will just know the facet name if the user clicked on a relative link, like next, previous, etc. It would be nice if the new page index was resolved, from the relative info, and set into the PaginatorActionEvent, before the event was broadcast, so all the info would be readily available in a single place.