function rollOver(key){
 tempPath = document.images[key].src;
 document.images[key].src=rollOverArray[key];
 rollOverArray[key] = tempPath;

}

var rollOverArray = new Array(); 

rollOverArray["navi1"] = "/images/navi1_on.gif";
rollOverArray["navi2"] = "/images/navi2_on.gif";
rollOverArray["navi3"] = "/images/navi3_on.gif";
rollOverArray["navi4"] = "/images/navi4_on.gif";
rollOverArray["navi5"] = "/images/navi5_on.gif";
rollOverArray["navi6"] = "/images/navi6_on.gif";
rollOverArray["navi7"] = "/images/navi7_on.gif";

rollOverArray["subnavi1"] = "images/submenu1_stay.gif";
rollOverArray["subnavi2"] = "images/submenu2_stay.gif";
rollOverArray["subnavi3"] = "images/submenu3_stay.gif";
rollOverArray["subnavi4"] = "images/submenu4_stay.gif";
rollOverArray["subnavi5"] = "images/submenu5_stay.gif";
rollOverArray["subnavi6"] = "images/submenu6_stay.gif";
rollOverArray["subnavi7"] = "images/submenu7_stay.gif";