function preload(){
	if (navigator.appVersion.charAt(0) >= "3") {
	img_max=imgName.length;
	for(idx=0; idx<img_max; idx++) {
		img[idx] = new Image();
		img[idx].src = baseDir + imgName[idx] + ".gif";
		}
	}
}
//rollover
function button(nam,o){
	if (navigator.appVersion.charAt(0) >= "3"){
		document.images[nam].src=baseDir+o+".gif";
	}
}