browserName = navigator.appName; browserVer = parseInt(navigator.appVersion);

if (browserName == "Netscape" && browserVer >= 3) { browserCheck = "ok"; }

else { 

    if (browserName == "Microsoft Internet Explorer" && browserVer >= 3) { browserCheck = "ok"; }

    else { browserCheck = "bad"; }

}

if (browserCheck == "ok") { 

b1a = new Image(); b1a.src = "but1.gif";
b1b = new Image(); b1b.src = "but1a.gif";
b2a = new Image(); b2a.src = "but2.gif";
b2b = new Image(); b2b.src = "but2a.gif";
b3a = new Image(); b3a.src = "but3.gif";
b3b = new Image(); b3b.src = "but3a.gif";
b4a = new Image(); b4a.src = "but4.gif";
b4b = new Image(); b4b.src = "but4a.gif";
b5a = new Image(); b5a.src = "but5.gif";
b5b = new Image(); b5b.src = "but5a.gif";
b6a = new Image(); b6a.src = "but6.gif";
b6b = new Image(); b6b.src = "but6a.gif";
b7a = new Image(); b7a.src = "but7.gif";
b7b = new Image(); b7b.src = "but7a.gif";
b8a = new Image(); b8a.src = "but8.gif";
b8b = new Image(); b8b.src = "but8a.gif";
}

function imgswap( Iname1, Iname2) { if (browserCheck == "ok") { document [Iname1].src
= eval(Iname2 + ".src"); } }