function home_newsletter() {
	var re_emptyall = new RegExp("^[ ]*$");
	
	if ( (document.forms[0].newsletter.value == '') || (re_emptyall.test(document.forms[0].newsletter.value)) ) {
		alert("Devi inserire l'indirizzo mail");
		document.forms[0].newsletter.focus();
		return;
	} else {
		document.forms[0].submit();
	}
}