// 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-001-over.jpg";
    img2on = new Image();
    img2on.src = "images/button-002-over.jpg";
    img3on = new Image();
    img3on.src = "images/button-003-over.jpg";
    img4on = new Image();
    img4on.src = "images/button-004-over.jpg";
    img5on = new Image();
    img5on.src = "images/button-005-over.jpg";
    img6on = new Image();
    img6on.src = "images/button-006-over.jpg";
    img7on = new Image();
    img7on.src = "images/button-007-over.jpg";
    img8on = new Image();
    img8on.src = "images/button-008-over.jpg";
    img9on = new Image();
    img9on.src = "images/button-009-over.jpg";
    img10on = new Image();
    img10on.src = "images/button-010-over.jpg";
    img11on = new Image();
    img11on.src = "images/button-011-over.jpg";
    
    img1off = new Image();
    img1off.src = "images/button-001.jpg";
    img2off = new Image();
    img2off.src = "images/button-002.jpg";
    img3off = new Image();
    img3off.src = "images/button-003.jpg";
    img4off = new Image();
    img4off.src = "images/button-004.jpg";
    img5off = new Image();
    img5off.src = "images/button-005.jpg";
    img6off = new Image();
    img6off.src = "images/button-006.jpg";
    img7off = new Image();
    img7off.src = "images/button-007.jpg";
    img8off = new Image();
    img8off.src = "images/button-008.jpg";
    img9off = new Image();
    img9off.src = "images/button-009.jpg";
    img10off = new Image();
    img10off.src = "images/button-010.jpg";
    img11off = new Image();
    img11off.src = "images/button-011.jpg";
    
  }

// 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");
    }
}