var app = navigator.appName.toLowerCase();
	var ver = parseFloat(navigator.appVersion);
	var ie = (app.indexOf("microsoft") != -1);
	var nn = (app.indexOf("netscape") != -1);
	var gecko = (navigator.userAgent.toLowerCase().indexOf("gecko") != -1);
	var ie4 = (ie && ver >= 4.0);
	var nn3 = (nn && ver >= 3.0);
	var scriptAllow = (ie4 || nn3);
	var dhtmlAllow = (ie4 || (nn && ver >= 4.0) || gecko);