Tree Grid :- showing total

Dear Ankur,
This is with reference to your excellent example:-
http://www.activewidgets.com/javascript.forum.18013.3/tree-grid.html

Now I have a problem - how to display the totoal value at the end of a column ?

When I use row constant or rowindices, I get only what is displayed - that means my tree may contain 10 rows, I have not expanded yet. But I want the total of all rows. Can you help please, thanks

Best
Ravion