if (document.images){
   topz = new Image;
   homez = new Image;
   backz = new Image;
   lnkz = new Image;
   topz.src = "./images/arctopz.gif";
   homez.src = "./images/archomez.gif";
   backz.src = "./images/arcbackz.gif";
   lnkz.src = "./images/awlnkz.gif";
   var docurl = document.URL;
   var num=docurl.indexOf(".htm");
   var code=docurl.substring(num-2,num)
   }
else {
topz = "";backz = "";homez="";
}
function xover(imagename){
var gifname = imagename;
if (imagename.substring(0,3)=="top"){gifname="arctop";}
if (imagename.substring(0,4)=="back"){gifname="arcback";}
if (imagename.substring(0,4)=="home"){gifname="archome";}
if (imagename.substring(0,3)=="lnk"){gifname="awlnk";}
document.images[imagename].src="./images/"+gifname+"z.gif";
}
function xout(imagename){
var gifname = imagename;
if (imagename.substring(0,3)=="top"){gifname="arctop";}
if (imagename.substring(0,4)=="back"){gifname="arcback";}
if (imagename.substring(0,4)=="home"){gifname="archome";}
if (imagename.substring(0,3)=="lnk"){gifname="awlnk";}
document.images[imagename].src="./images/"+gifname+".gif";
}