I'm making a web site with an expandable menu in the left frame and the usual crap in the right frame. How do I switch out the contents of the right frame *only* whenever a menu option is clicked?

Right now, a menu option calls a dupe of the home page (only with new text in the right frame). It works just fine but I'm calling a new menu as well, and when I do, it reinitializes to a closed state.

If I could switch out just the contents of the right frame, the menu (being untouched) would remain expanded and users would be able to see the list of sup-topics at all times.

Thanks - rev