bName = navigator.appName;
bVer = parseInt(navigator.appVersion);
    if ((bName == "Netscape" && bVer >= 3) || 
        (bName == "Microsoft Internet Explorer" && bVer >= 4)) br = "n3"; 
    else br = "n2";
    if (br== "n3") { 

    img1on = new Image();                    
    img1on.src = "imgs/head/m1a.gif";      
    img1off = new Image();              
    img1off.src = "imgs/head/m1.gif"; 

    img2on = new Image();                    
    img2on.src = "imgs/head/m2a.gif";      
    img2off = new Image();              
    img2off.src = "imgs/head/m2.gif";

    img3on = new Image();                    
    img3on.src = "imgs/head/m3a.gif";      
    img3off = new Image();              
    img3off.src = "imgs/head/m3.gif";

    img4on = new Image();                    
    img4on.src = "imgs/head/m4a.gif";      
    img4off = new Image();              
    img4off.src = "imgs/head/m4.gif"; 

    img5on = new Image();                    
    img5on.src = "imgs/head/m5a.gif";      
    img5off = new Image();              
    img5off.src = "imgs/head/m5.gif";
    
    img6on = new Image();                    
    img6on.src = "imgs/head/m6a.gif";      
    img6off = new Image();              
    img6off.src = "imgs/head/m6.gif";
    
    img7on = new Image();                    
    img7on.src = "imgs/head/m7a.gif";      
    img7off = new Image();              
    img7off.src = "imgs/head/m7.gif";
    
    img8on = new Image();                    
    img8on.src = "imgs/head/m8a.gif";      
    img8off = new Image();              
    img8off.src = "imgs/head/m8.gif";
    
    img9on = new Image();                    
    img9on.src = "imgs/head/m9a.gif";      
    img9off = new Image();              
    img9off.src = "imgs/head/m9.gif";

}
function imgAct(imgName) {
    if (br == "n3") {
    document[imgName].src = eval(imgName + "on.src");
    }
}
function imgInact(imgName) {
    if (br == "n3") {
    document[imgName].src = eval(imgName + "off.src");
    }
}