Box is different height in IEWIN then on Firefox! Can anyone tell me why?

http://www.coloradocollege.edu/ccinn/

The orange box surrounding the text is set to a height of 342px, but it’s taller in Firefox (by about 20px) then it is in IE. There is no top or bottom padding… so I don’t see what the problem could be.

Turns out its actually the menus that differ in height, not the orange box. I need to use padding for the menus, but how can I make the padding the same in IE6PC and firefox?