function getXmlHttpRequestObject() {
	if(window.XMLHttpRequest){
    	return new XMLHttpRequest();
 	}else if(window.ActiveXObject){
    	return new ActiveXObject("Microsoft.XMLHTTP");
 	}else{
    	alert("Your browser doesn't support the XmlHttpRequest object.");
 	}
}

var receiveReq = getXmlHttpRequestObject();

function makeRequest(url, param) {

	if(receiveReq.readyState == 4 || receiveReq.readyState == 0){
	   	receiveReq.open("POST", url, true);
	   	receiveReq.onreadystatechange = updatePage; 
	
	   	receiveReq.setRequestHeader("Content-type", "application/x-www-form-urlencoded");
	   	receiveReq.setRequestHeader("Content-length", param.length);
	   	receiveReq.setRequestHeader("Connection", "close");
	
	   	receiveReq.send(param);
	}
  
}

function updatePage(){
	if(receiveReq.readyState == 4){
      
   		if(receiveReq.responseText=="ok"){
   			document.frmCaptcha.submit();
   		}else{
   			document.getElementById('result').innerHTML = receiveReq.responseText;
	   		img = document.getElementById('imgCaptcha'); 
	   		//img.src = 'captcha/create_image.php?' + Math.random();
	   		img.src = 'captcha/CaptchaSecurityImages.php?width=100&height=40&characters=5&'+ Math.random();
   		}
 	}
}

function getParam(theForm) {

 	var url = 'captcha/captcha.php';
 	var postStr = theForm.txtCaptcha.name + "=" + encodeURIComponent( theForm.txtCaptcha.value );
 	makeRequest(url, postStr);
 	
}