Flash overlap iframe

I have a header that contains a flash menu. I have it in a div so that when a button is rolled over there is a drop down menu that overlaps the iframe below it. When the iframe contains only HTML this works out perfect. However, if the iframe contains flash, the flash in the iframe is set on top of the drop down menu.

I was hoping someone has dealt with this before and has a solution. I’m thinking z-index, but i haven’t gotten it to work so far.

Thanks for your help!