Child theme custom dropdown menu IE7 problem

Hi there,

I am currently developing a site for a client using version 3.2.1. It looks great in Firefox, Chrome, and IE9. But, of course, earlier versions of IE are causing issues; specifically, my custom menu dropdowns are not working.

The site: http://smartsbroadcast.com/redesign2011

NOTE: This site is still in development. I created and am using a child theme based on Twenty Ten.

From searching the forums, I know this is a fairly common issue, and I have tried several remedies, including changing the z-index for the menu, setting the <doctype>, and a couple of different script possibilities, but nothing seems to work.

Any and all assistance will be greatly appreciated. Thanks in advance.