//detect browser:
     browserName = navigator.appName;
     browserVer = parseInt(navigator.appVersion);
     if (browserName == "Netscape" && browserVer >= 3) browserVer = "1";
     else if (browserName == "Microsoft Internet Explorer" && browserVer == 4) browserVer
     = "1";
	 else if (browserName == "Opera" && browserVer == 5) browserVer
     = "1";
     else browserVer = "2";

     //preload images:
     if (browserVer == 1) {
     b1 = new Image(150,155);
     b1.src = "images/email1.jpg";
     b2 = new Image(150,155);
     b2.src = "images/email2.jpg";
     }
	 
	 //Notice that you put the width and height in the preload area
	 
	 //image swapping function:
     function hiLite(imgDocID, imgObjName, comment) {
     if (browserVer == 1) {
     document.images[imgDocID].src = eval(imgObjName + ".src");
     window.status = comment; return true;
     }}