Horizontal Spry MenuBar completely broken in IE6

Question

I have a horizontal spry menu bar on a site. I have done some customization, but mainly styling - and nothing really with positioning, except having the subs appear above the main bar as opposed to below. The bar works perfectly fine in ALL major browsers, but then we get to IE6 and it is completely broken. I have no idea why. The background of the main bar is visible in IE6, but none of the submenu items  - no text or anything. The only thing that happens is that the cursor changes as if it is picking up a link, but nothing happens when I click on it.
The site is www.alpineonline.com.
Here is a link to a couple of images that shows it working and not working: http://paradigmforward.com/alpine/html/spryexample.html
It is obviously urgent that I get this fixed, but have no idea where to start. I must say that based on some of the other threads on this forum, I do not have high hopes that anyone will even respond, but it is worth a shot (i.e. - saw other users having the same issue, but no one ever responded to any of them!)
Thanks!

Answer 1

ADDITIONAL INFO -
I just discovered two more pieces of information that may be of value in resolving this.
As I mentioned, when you roll the mouse over the big blue bar in IE6, the cursor changes as if there is a link there. I just discovered that on one of the spots on this blue bar (just above the 2009 in the footer) is where a submenu displays. This submenu displays WAY over to the right off the site.
Additionally, I am getting 5 CSS validation errors all related to this part of the CSS: (line numbers for reference)
172       /* HACK FOR IE: to make sure the sub menus show above form controls, we underlay each submenu with an iframe */
173       ul.MenuBarHorizontal iframe
174       {
175           position: absolute;
176           z-index: 1010;
177           filter:alpha(opacity:0.1);
178       }
179       /* HACK FOR IE: to stabilize appearance of menu items; the slash in float is to keep IE 5.0 from parsing */
180       @media screen, projection
181       {
182          ul.MenuBarHorizontal li.MenuBarItemIE
183          {
184           display: inline;
185           f\loat: left;
186          background-color: #536186;
187           }
188        }
Here are the errors:
177 ul.MenuBarHorizontal iframe  "attempt to find a semi-colon before the property name. add it"
0     ul.MenuBarHorizontal iframe  "Parse error Null"
177 ul.MenuBarHorizontal iframe   "Property opacity doesn't exist in CSS level 2.1 but exists in [css3] :                                               0.1"
177 ul.MenuBarHorizontal iframe   "Parse Error                                              0.1);"
177 ul.MenuBarHorizontal iframe   "Property opacity doesn't exist in CSS level 2.1 but exists in [css3] :                                               0.1"
177 ul.MenuBarHorizontal iframe   "Parse Error                                              }"
Also, I failed to mention that I am using CS4, so I am sure the Spry Framework is the latest version available.
Hopefully fixing these errors will solve the problem! Just not sure how to do that.