Now, I'm no expert - bear that in mind. I have 90% of a solution for you though.
What I've managed to do is get the submenus showing in IE - however, the way I have it the first highlighted word - the kind of menu heading - changes back to black. A better person than me will be able to fix that. Hmmm... I'm not explaining this very well - please have a look and you'll see what I mean.
Another thing though - and this is good - your tables weren't looking very good in IE - too narrow. I've extended them.