var imageFiles_y644_4 = new Array();
imageFiles_y644_4['0'] = new Array ('_images/y644_Mule_Ears.gif', '_images/y644_Mule_EarsMouseover.gif');

function image_on_y644_4 (position) {
   var doc = eval("document.imagey644_4" + position);
   doc.src = imageFiles_y644_4[position][1];
}

function image_off_y644_4 (position) {
   var doc = eval("document.imagey644_4" + position);
   doc.src = imageFiles_y644_4[position][0];
}