var ajax = new sack();

function whenCompleted(){
	var e = document.getElementById('tdMain'); 
	if (ajax.responseStatus){
		var string = ajax.response;
	} else {
		var string = "";
	}
	e.innerHTML = string;	
}

function doit(){
	var form = document.getElementById('frmNewsletter');
	if((form.name.value == '') || (form.name.value == 'Naam')){alert('Vul aub je naam in!');return false;}
	if((form.email.value == '') || (form.email.value == 'Email')){alert('Vul aub je e-mail adres in!');return false;}
	ajax.setVar("name", form.name.value); // recomended method of setting data to be parsed.
	ajax.setVar("email", form.email.value);
	ajax.requestFile = "sendNewsletter.php";
	ajax.method = 'post';
	ajax.element = 'tdMain';
	ajax.onCompletion = whenCompleted;
	ajax.runAJAX();
}