When container absolutely positioned, IE displays submenus to single position

I'm having some trouble with a horizontal menu. What I want to do is move the markup to the bottom of the page (in preference to adding a skip nav link). What I did to accomplish this was absolutely position the container div for the menu inside of a relatively positioned element. The menu positions correctly in every browser I've tested, but when a main item is highlighted in IE, the submenus and sub-submenus appear to be positioned with the container (top:0;left:0 possibly plus the offsets. This makes the menu completely unusable. How can I get IE to follow the positioning rules in this circumstance?

the example link is:
http://catalog.cantonpl.org:2082/