isNN3 = (navigator.appName == "Netscape" && parseInt(navigator.appVersion)>= 3);
isIE4 = (navigator.appName == "Microsoft Internet Explorer" && parseInt(navigator.appVersion) > 3);


if(isNN3 || isIE4) {
var homedn = new Image();
homedn.src = '../images/home_off.gif';
var homeup = new Image();
homeup.src = '../images/home_on.gif';

var toursdn = new Image();
toursdn.src = '../images/tours_off.gif';
var toursup = new Image();
toursup.src = '../images/tours_on.gif';

var destinationsdn = new Image();
destinationsdn.src = '../images/destinations_off.gif';
var destinationsup = new Image();
destinationsup.src = '../images/destinations_on.gif';

var tripdn = new Image();
tripdn.src = '../images/trip_off.gif';
var tripup = new Image();
tripup.src = '../images/trip_on.gif';

var communitydn = new Image();
communitydn.src = '../images/community_off.gif';
var communityup = new Image();
communityup.src = '../images/community_on.gif';

var resourcesdn = new Image();
resourcesdn.src = '../images/resources_off.gif';
var resourcesup = new Image();
resourcesup.src = '../images/resources_on.gif';

}
function act(imgName) {
if(isNN3 || isIE4)
document[imgName].src = eval(imgName + 'up.src')
}

function inact(imgName) {
if(isNN3 || isIE4) 
document[imgName].src = eval(imgName + 'dn.src')
}