function chk_captcha(txt)
{
	
	var ajaxRequest;  // The variable that makes Ajax possible!
	
	try{
		// Opera 8.0+, Firefox, Safari
		ajaxRequest = new XMLHttpRequest();
	} catch (e){
		// Internet Explorer Browsers
		try{
			ajaxRequest = new ActiveXObject("Msxml2.XMLHTTP");
		} catch (e) {
			try{
				ajaxRequest = new ActiveXObject("Microsoft.XMLHTTP");
			} catch (e){
				// Something went wrong
				alert("Your browser broke!");
				return false;
			}
		}
	}
	// Create a function that will receive data sent from the server
	ajaxRequest.onreadystatechange = function(){
	//alert(ajaxRequest.readyState);
	//console.log(ajaxRequest.readyState);
		if(ajaxRequest.readyState == 4){
		
			captchaerror=ajaxRequest.responseText;
			//alert(chk);
			
		}
	}
	
	var queryString = "?txt=" + txt;
	ajaxRequest.open("GET", "chk_captcha.php" + queryString, true);
	ajaxRequest.send(null);
	
}