Problem with dropdown in IE8 Compatibility Mode

Question

I am having a problem with my site in IE8 Compatibility mode. Below is a URL where you get the basic idea of what my websites dropdowns look like. The dropdowns are done in CSS and when you hover over one dropdown the submenu for the dropdown expands under the dropdown to the right of it. It works correctly in Safari, Chrome, Firefox, and normal IE8. But when you go to compatibility mode it isn't working correctly. Any help would be much appreciated.

http://jsfiddle.net/h5xZT/28/

Thanks

Answer 1

Putting display:block; on the MAINMENUBAR class fixes the issue:

http://jsfiddle.net/h5xZT/29/