in your css try adding ../ to the locations of your images as in :
Code:
#main-nav dt#contact a { width: 106px; background-image: url(/images/nav/contact.gif); }
to become
Code:
#main-nav dt#contact a { width: 106px; background-image: url(../images/nav/contact.gif); }
I think that's it, i dunno!