i can't figure out this code that's supposed to make an image that changes when the mouse is over it<SCRIPT TYPE="text/javascript"><!--var rollOverArr=new Array();function setrollover(OverImgSrc,pageImageName){if (! document.images)return;if (pageImageName == null) pageImageName = document.images[document.images.length-1].name;rollOverArr[pageImageName]=new Object;rollOverArr[pageImageName].overImg = new Image;rollOverArr[pageImageName].overImg.src=OverImgSrc;}function rollover(pageImageName){if (! document.images)return;if (! rollOverArr[pageImageName])return;if (! rollOverArr[pageImageName].outImg) { rollOverArr[pageImageName].outImg = new Image; rollOverArr[pageImageName].outImg.src = document.images[pageImageName].src; }document.images[pageImageName].src=rollOverArr[pageImageName].overImg.src;}function rollout(pageImageName){if (! document.images)return;if (! rollOverArr[pageImageName])return;document.images[pageImageName].src=rollOverArr[pageImageName].outImg.src;}//--></SCRIPT>