arrowOn = new Image();
arrowOn.src = "i/ar_on.gif";
arrowOff = new Image();
arrowOff.src = "i/ar_off.gif";

function swapNav(name) {
  document[name].src = (document[name].src.indexOf('_on') != -1) ? 'i/ar_off.gif' : 'i/ar_on.gif';
}

function validateForm() {
	var email = document.emailupdates.email.value;
	if (email == "") {
		alert("Please enter your email address.");
		return false;
	}
	else if ( (email.indexOf("@") == -1) || (email.indexOf(".") == -1) ) {
		alert("Please enter a valid email address.");
		return false;
	}
	return true;
}