function GetXmlHttpObject(handler) { 
	var objXmlHttp = null;

	if (navigator.userAgent.indexOf("MSIE") >= 0) { 
		var strName="Msxml2.XMLHTTP";
		if (navigator.appVersion.indexOf("MSIE 5.5") >= 0) {
			strName="Microsoft.XMLHTTP";
		} 
		try { 
			objXmlHttp = new ActiveXObject(strName);
			objXmlHttp.onreadystatechange = handler;
			return objXmlHttp;
		} catch(e) { 
			alert("Error. Scripting for ActiveX might be disabled");
			return;
		} 
	} 
	if (navigator.userAgent.indexOf("Mozilla") >= 0) {
		objXmlHttp = new XMLHttpRequest();
		objXmlHttp.onload = handler;
		objXmlHttp.onerror = handler;
		return objXmlHttp;
	}
} 


function checkCaptcha(frmObj) {
	var url = "checkCaptcha.asp?c=" + frmObj.value;
	
	xmlHttp = GetXmlHttpObject(stateChanged);
	xmlHttp.open("GET", url , true);
	xmlHttp.send(null);
}

function stateChanged()  {
   if (xmlHttp.readyState==4 || xmlHttp.readyState=="complete") {
		ajSub(xmlHttp.responseText);
	}
}