function checkEmail(){
	httpObject = getHTTPObject();
	if (httpObject != null) 
	{
		if (!document.getElementById('email').value== ""){
			httpObject.open("GET", "validate_email.php?email="+document.getElementById('email').value, true);
			httpObject.send(null);
			httpObject.onreadystatechange = setImage;
		}
		else
		{
			document.getElementById('emailflag').innerHTML = "<img src=\"images/failure.gif\">";
		}
	}
}
function getHTTPObject()
{
	if (window.ActiveXObject) return new ActiveXObject("Microsoft.XMLHTTP");
	else if (window.XMLHttpRequest) return new XMLHttpRequest();
	else 
	{
	alert("Your browser does not support AJAX.");
	return null;
	}
}
function setImage()
{
if(httpObject.readyState == 4)
	{
	document.getElementById('emailflag').innerHTML = httpObject.responseText;
	}	
}