if (document.images) {
		
aboutVZoff= new Image; 
aboutVZoff.src="/images/head/navavof.jpg"; 
prod_servoff= new Image; 
prod_servoff.src="/images/head/navpson.jpg"; 
customeroff= new Image; 
customeroff.src="/images/head/navcsof.jpg"; 

aboutVZon= new Image; 
aboutVZon.src="/images/head/navavhi.jpg"; 
prod_servon= new Image; 
prod_servon.src="/images/head/navpsho.jpg"; 
customeron= new Image; 
customeron.src="/images/head/navcshi.jpg"; 
}
function rollOver (i) {
        if (document.images) {
   if (document[i].src == eval(i + "off.src")) {
    document[i].src = eval(i + "on.src");
   } else {
    document[i].src = eval(i + "off.src");
   }
        }
}