upImage = new Image();
upImage.src = "images/spider-gene1.gif";
downImage = new Image();
downImage.src = "images/spider-gene2.gif"
normalImage = new Image();
normalImage.src = "images/spider-gene.gif";
function changeImage()
{
document.images["jsbutton"].src= "images/spider-gene1.gif";
return true;
}
function changeImageBack() 
{
 document.images["jsbutton"].src = "images/spider-gene.gif";
 return true;
}
function handleMDown()
{
 document.images["jsbutton"].src = "images/spider-gene2.gif";
 return true;
}
function handleMUp()
{
 changeImage();
 return true;
}