function checkCaptcha(value, buttonId) {
	if (window.XMLHttpRequest) {
		var req = new XMLHttpRequest();
	} else if (window.ActiveXObject) {
		var req = new ActiveXObject('Microsoft.XMLHTTP');
	}
	var url;
	url = '/captcha.php?action=check&value='+value;
	req.open('GET', url, true);
	req.onreadystatechange = function() {
		if (req.readyState == 4) {
			var response = req.responseText;
			if(response == 1) {
				document.getElementById(buttonId).disabled = false;
			}else{
				document.getElementById(buttonId).disabled = true;
			}
		}
	}
	req.send(null);				
	return false;
}