var revert = new Array();
var inames = new Array('nav_general2', 'nav_course', 'nav_group', 'nav_faq', 'nav_contact', 'nav_store2', 'nav_home', 'nav_shopping', 'nav_checkout');

if (document.images) {
  var flipped = new Array();
  for(i=0; i< inames.length; i++) {
    flipped[i] = new Image();
    flipped[i].src = "/media/images/site/"+inames[i]+"-over.gif";
  }
}

function over(num) {
  if(document.images) {
    revert[num] = document.images[inames[num]].src;
    document.images[inames[num]].src = flipped[num].src;
  }
}
function out(num) {
  if(document.images) document.images[inames[num]].src = revert[num];
}