function addEmail(){
	if($('email_address')){
		if(isEmail($('email_address').value)){
			var url = 'add.php';
			var pars = 'email='+$('email_address').value;
			var target = 'email_signup';
			var myAjax = new Ajax.Updater(target, url, { method: 'post', parameters: pars, onComplete: hideForm });
		} else {
			alert('Please enter a valid email address.');
		}
	}
	return false;
}

function isEmail(addy) {
	var form_value = addy;
	if (/^\w+([\.-]?\w+)*@\w+([\.-]?\w+)*(\.\w{2,3})+$/.test(form_value)){
		return true;
	} else {
		return false;
	}
}

function hideForm(){
	$('email_signup').innerHTML = 'Your email address has been added.';
	$('email_address').value = '';
}