function detectIE6()
{
	var browser = navigator.appName;
	if (browser == "Microsoft Internet Explorer")
	{
		var b_version = navigator.appVersion;
		var re = /\MSIE\s+(\d\.\d\b)/;
		var res = b_version.match(re);
		if (res[1] <= 6)
		{
			return true;
		}
	}
		return false;
}

function detectMacXFF() {
  var userAgent = navigator.userAgent.toLowerCase();
  if (userAgent.indexOf('mac') != -1 && userAgent.indexOf('firefox')!=-1) {
    return true;
  }
}