Communication from html to an swf?

Alright, i hope somebody can help me out, especially considering that i’m a graphic designer with
i’m building this site and the client as usual is been a hassle. After developing half the site now he wants to have some extra features. So the problem is, i have a menu in flash that loads content into an iFrame. Now i need to make the swf go to a diffrent scene by pressing a button located in the iFrame and at the same time the button has to load content into its parent iframe, i’ve read several similar posts in different forums but none seems to work for me.

Any ideas??

Thanks in advanced!