var ns = false;
if (((navigator.appName == "Netscape") && (parseInt(navigator.appVersion) >= 3 )) || 
    ((navigator.appName == "Microsoft Internet Explorer") && (parseInt(navigator.appVersion) >= 4 )))
   {ns=true}

if (ns)
{
a1 = new Image();
a1.src = "img/m2.gif";
a2 = new Image();
a2.src = "img/m2_on.gif";
b1 = new Image();
b1.src = "img/m4.gif";
b2 = new Image();
b2.src = "img/m4_on.gif";
c1 = new Image();
c1.src = "img/m6.gif";
c2 = new Image();
c2.src = "img/m6_on.gif";
d1 = new Image();
d1.src = "img/m8.gif";
d2 = new Image();
d2.src = "img/m8_on.gif";
e1 = new Image();
e1.src = "img/m10.gif";
e2 = new Image();
e2.src = "img/m10_on.gif";
f1 = new Image();
f1.src = "img/m12.gif";
f2 = new Image();
f2.src = "img/m12_on.gif";
g1 = new Image();
g1.src = "img/m14.gif";
g2 = new Image();
g2.src = "img/m14_on.gif";
h1 = new Image();
h1.src = "img/m16.gif";
h2 = new Image();
h2.src = "img/m16_on.gif";

}
function zmena(imgDocID,imgObjName) {
if (ns) {
document.images[imgDocID].src = eval(imgObjName + ".src")
}}