var buildDir = "menu/";
var ie4 = false, ie5_mac = false, ie55 = false;
var nn4 = false, dom = false, opera = false, safari = false;

var agent = navigator.userAgent.toLowerCase();

if (agent.indexOf("opera") != -1){
  opera = true;
}
else if (agent.indexOf("safari") != -1){
  safari = true;
}
else if (document.all){
  var version = parseFloat(agent.substr(agent.indexOf("msie")+5, 3));

  if (agent.indexOf("mac") != -1 && version >= 5){
    ie5_mac = true;
  } else {
    if (version >= 5.5){
	  ie55 = true;
	}
	else if (version >= 4){
	  ie4 = true;
	}
  }
}
else if (navigator.appName == "Netscape" && parseInt(navigator.appVersion) >= 4 && parseInt(navigator.appVersion) < 5){
	nn4 = true;
}
else if (document.getElementById){
	dom = true;
}

var blank = new Image();
blank.src = buildDir + "blank.gif";

if (ie4){
	document.write('<script type="text/javascript" src="' + buildDir + 'ie4-build.js"></script>');
}
else if (ie5_mac){
	document.write('<script type="text/javascript" src="' + buildDir + 'ie5m-build.js"></script>');
}
else if (ie55){
	document.write('<script type="text/javascript" src="' + buildDir + 'ie55-build.js"></script>');
}
else if (nn4){
	document.write('<script type="text/javascript" src="' + buildDir + 'ns4-build.js"></script>');
}
else if (dom){
	document.write('<script type="text/javascript" src="' + buildDir + 'dom-build.js"></script>');
}
else if (opera){
	document.write('<script type="text/javascript" src="' + buildDir + 'ie55-build.js"></script>');
}
else if (safari){
	document.write('<script type="text/javascript" src="' + buildDir + 'saf-build.js"></script>');
} else {
  alert("Your browser doesn't support this script.");
  location.href = buildDir + "upgrade.html";
  document.write('<script type="text/javascript" src="' + buildDir + 'no-build.js"></script>');
}