//Tweak these two values if you need
var yoff = 340;
var xoff = 60;
var ie = document.all;

function showPic(e, src) {
  if(!e) e = window.event;
  var pic = document.getElementById('thumbPic');

  pic.src = src;
  pic.style.display = '';

  var y = (ie) ? e.y+document.body.scrollTop : e.clientY+yoff;
  var x = (ie) ? e.x+document.body.scrollLeft+xoff : e.clientX + xoff;
  pic.style.position = 'absolute';
  pic.style.top = y + 'px';
  pic.style.left = x + 'px';
}

function hidePic() {
  var pic = document.getElementById('thumbPic');
  pic.style.display = 'none';
  pic.src = 'images/null_image.gif';
}