function subscribe()
{
	var	radio_subscribe = document.getElementById("subscribe");
	var	radio_unsubscribe = document.getElementById("unsubscribe");
	var	email = document.getElementById("email");

	if(!radio_subscribe.checked && !radio_unsubscribe.checked)
	{
		alert(error_select_subscribe_unsubscribe);
		return false;
	}

	var rge=new RegExp("^([_a-z0-9-]+)(\.[_a-z0-9-]+)*@([a-z0-9-]+)(\.[a-z0-9-]+)*(\.[a-z]{2,4})$","i");
	if(!email.value || email.value.search(rge) != 0)
	{
		alert(error_email);
		email.focus();
		return false;
	}

	if(radio_subscribe.checked)
	{
		action = 'subscribe';
		alert(success_subscribe);
	}
	else if(radio_unsubscribe.checked)
	{
		action = 'unsubscribe';
		alert(success_unsubscribe);
	}

	xajax_subscribe(action, email.value);
}