var imageFiles_ad_13 = new Array();
imageFiles_ad_13['0'] = new Array ('_images/ad_Home.gif', '_images/ad_HomeMouseover.gif');

function image_on_ad_13 (position) {
   var doc = eval("document.imagead_13" + position);
   doc.src = imageFiles_ad_13[position][1];
}

function image_off_ad_13 (position) {
   var doc = eval("document.imagead_13" + position);
   doc.src = imageFiles_ad_13[position][0];
}