browserName = navigator.appName;
browserVer = parseInt(navigator.appVersion);
if ( (browserName == "Netscape" && browserVer >= 6) ||
(browserName == "Microsoft Internet Explorer" && browserVer >= 6))
compat = "true";
else compat = "false";
function back() {
if (compat == "true") {
history.go(-1)
}
}