// Detect if browser is Netscape 3 + or IE 4 +.
bName = navigator.appName;
bVer = parseInt(navigator.appVersion);
    if ((bName == "Netscape" && bVer >= 3) || 
        (bName == "Microsoft Internet Explorer" && bVer >= 4)) br = "n3"; 
    else br = "n2";
// Create image objects, preload all active and inactive images.
    if (br== "n3") { 

    img1on = new Image();                    
    img1on.src = "images/button_welcome2.gif";      
    img1off = new Image();              
    img1off.src = "images/button_welcome.gif";
	
	img2on = new Image();                    
    img2on.src = "images/button_products2.gif";      
    img2off = new Image();              
    img2off.src = "images/button_products.gif";
	
	img3on = new Image();                    
    img3on.src = "images/button_about2.gif";      
    img3off = new Image();              
    img3off.src = "images/button_about.gif";

	img4on = new Image();                    
    img4on.src = "images/button_contact2.gif";      
    img4off = new Image();              
    img4off.src = "images/button_contact.gif";
	
}
// Function to "activate" images.
function imgAct(imgName) {
    if (br == "n3") {
    document[imgName].src = eval(imgName + "on.src");
    }
}
// Function to "deactivate" images.
function imgInact(imgName) {
    if (br == "n3") {
    document[imgName].src = eval(imgName + "off.src");
    }
}