Q: First of all we would like to mention that we are incredibly happy with the unlimited version of your css3 image button.
However, today we ran into a problem with incorporating a menu.
We somehow succeeded in putting the css menu into an iFrame but then the Sub Menus do not display resp. are hidden.

A: Unfortunately css3 image button drop down menus don't overlap frames.
Try to insert menu into DIV or TABLE tags. Submenus will work correctly.

You can try also to use Deluxe Menu if you want to use frames:
http://deluxe-menu.com/
http://deluxe-menu.com/cross-frame-mode-sample.html