var prevId = 'a01Div'; //previous active id
var fldImg = 'images/';
var photoId = 'ph';
var photoExt = '.jpg';

function mouseOver(o)
{
	if(o==null || o.className=='') return;
	var aid = o.className, divId = aid+'Div';
	var div = document.getElementById(divId);
	var img = document.getElementById(photoId);
	div.style.display = 'block';
	img.src = fldImg + photoId + aid + photoExt;
	if(prevId!=divId) document.getElementById(prevId).style.display = 'none';
	prevId = aid+'Div';
}