function versionInfo() {
	this.xhtml = "";
	this.version = "";
	this.importance = "";
}

function detectDoctype() {
	var re = /\s+(X?HTML)\s+([\d\.]+)\s*([^\/]+)*\//gi;
	var myVersionInfo = new versionInfo();
	/*********************************************
	Just check for internet explorer.
	**********************************************/
	if (typeof document.namespaces != "undefined") {
		if (document.all[0].nodeType == 8)
			re.exec(document.all[0].nodeValue);
	else
		return null;
	}
	else {
		if (document.doctype != null)
			re.exec(document.doctype.publicId);
	else
		return null;
	}
	myVersionInfo.xhtml = RegExp.$1;
	myVersionInfo.version = RegExp.$2;
	myVersionInfo.importance = RegExp.$3;
	
	return myVersionInfo;
}

/* var myVersionInfo = detectDoctype();
if(myVersionInfo != null) {
	alert(myVersionInfo.xhtml);
	alert(myVersionInfo.version);
	alert(myVersionInfo.importance);
}
else{
	alert("There is no DOCTYPE in the code!");
} */