function validar_tecla(e) {
	var tecla;
	var caracter;
		
	if (window.event || !e.which) {
		tecla = e.keyCode;
	} else {
		return true;
	};

	caracter = String.fromCharCode(tecla);
	caracter = caracter.toLowerCase();

	if (caracter!=' ' && caracter!='\'' && caracter!='\"' && caracter!=';' && caracter!=':' && caracter!='#') {
		return true;
	} else {
		return false;
	};
}

function echeck(str) {
	var at="@";
	var dot=".";
	var lat=str.indexOf(at);
	var lstr=str.length;
	var ldot=str.indexOf(dot);

	if ((str.indexOf(at)==-1) ||
	((str.indexOf(at)==-1 || str.indexOf(at)==0 || str.indexOf(at)==lstr)) ||
	((str.indexOf(dot)==-1 || str.indexOf(dot)==0 || str.indexOf(dot)==lstr)) ||
	(str.indexOf(at,(lat+1))!=-1) ||
	((str.substring(lat-1,lat)==dot || str.substring(lat+1,lat+2)==dot)) ||
	(str.indexOf(dot,(lat+2))==-1) ||
	(str.indexOf(" ")!=-1)) {
		return false;
	} else {
		return true;
	};
}	
function validar_news(){
			var nombre_news = document.getElementById('form_news').nombre_news;
			var email_news = document.getElementById('form_news').email_news;
			
			if (nombre_news.value.length<1 || nombre_news.value=='Nombre y Apellido') {
				alert("You must enter a name.");
				nombre_news.focus();
				return false;
			} else 	if (email_news.value.length<1 || nombre_news.value=='e-mail') {
				alert("You must enter an email");
				email_news.focus();
				return false;
			} else if ((email_news.value.length>0) && (echeck(email_news.value)==false)) {
				alert("The e-mail isn't valid.");
				email_news.focus();
				return false;
			} else {
				return true;
			};
 		};
		
document.getElementById('form_news').onsubmit = validar_news;