if(document.images) {
     
		
		homeoff = new Image();
		homeoff.src = "images/nuevos/homeboton.jpg";
		homeover = new Image();
		homeover.src = "images/nuevos/homebotonon.jpg";
				
		fotosoff = new Image();
		fotosoff.src = "images/nuevos/fotosboton.jpg";
		fotosover = new Image();
	    fotosover.src = "images/nuevos/fotosbotonon.jpg";
		
		proveedoresoff = new Image();
		proveedoresoff.src = "images/nuevos/proveedoresboton.jpg";
		proveedoresover = new Image();
	    proveedoresover.src = "images/nuevos/proveedoresbotonon.jpg";

        contactooff = new Image();
		contactooff.src = "images/nuevos/contactoboton.jpg";
		contactoover = new Image();
		contactoover.src = "images/nuevos/contactobotonon.jpg";

        librooff = new Image();
		librooff.src = "images/nuevos/libroboton.jpg";
		libroover = new Image();
		libroover.src = "images/nuevos/librobotonon.jpg";
        	
}

function onoff(imgName,state) {
        if(document.images) {               
		document.images[imgName].src = eval(imgName+state+".src");
        }
}