Flash content in an iframe always appears on top

[ExpDisease]

http://www.eczaderm.com/

I have an iframe that is linked to source.html and that source.html has a swf gallery in it. As you can see in this example the top menu stays behind the flash gallery. I tried with giving iframe z-index:-1 but it didin't work. How can I fix this ?

Ups I figured the solution that wmode must set to transparent . Thanks anyway