How to make scroll bars visible and to f

Dear friends
My query is
I have developed a site with frameset compatible to IE. The site is working fine in IE6 and Netscape6.
But the problem is the site is not working fine when it is opened in Netscape4. Since i used the frameset, the scroll bars are not functioning well.
Can u tell me how to make the scrollbar to visible and function in Netscape4 without altering the complete code which i had previously done.