img1on = new Image();
img1on.src = "./images/menu/left-menu-1.gif";  
img2on = new Image();
img2on.src = "./images/menu/left-menu-2.gif";  
img3on = new Image();
img3on.src = "./images/menu/left-menu-3.gif";  
img4on = new Image();
img4on.src = "./images/menu/left-menu-4.gif";  
img5on = new Image();
img5on.src = "./images/menu/left-menu-5.gif";  
img6on = new Image();
img6on.src = "./images/menu/left-menu-6.gif";
img7on = new Image();
img7on.src = "./images/menu/left-menu-7.gif";
img8on = new Image();
img8on.src = "./images/menu/left-menu-8.gif";

img1off = new Image();
img1off.src = "./images/menu/left-menu-off.gif";  

function mouseOn(imgName1, imgName)
{
 document[imgName1].src = eval(imgName + "on.src");
}
function mouseOff(imgName)
{
 document[imgName].src = eval(imgName + "off.src");
}