I think its only possible if you do the scrolling yourself and do not rely on the <a name=...> tag.
You can probably do something like (untested):
anchor.addClickHandler(new ClickHandler() {
public void onClick(ClickEvent event) {
Widget jumpTo = getWidgetYouWantToScrollTo();
jumpTo.getElement().scrollIntoView(); //Version 1
scrollPanel.setVerticalScrollPosition(jumpTo.getElement().getOffsetTop()); //Version 2
Window.scrollTo(0, jumpTo.getElement().getOffsetTop()); //Version 3
}
});
-- J.