how to find the total number of pages in smartforms

Dear experts,

        I have design a smartform with only one page,

and one of window(Secondly window) should be displayed according to current page number and total pages

when I debug the code  i find SFSY-PAGE and SFSY-FORMPAGES

1, SFSY-PAGE = 1 and SFSY-FORMPAGES =1

2, SFSY-PAGE = 2 and SFSY-FORMPAGES =2

3, SFSY-PAGE = 3 and SFSY-FORMPAGES =3

i need the total number of pages to print the window basdes on the total number of pages.

Any help would be highly appreciated.

thanks in advance.

Raja.