// JavaScript Document

function checkEmail(email) {
	var email;
	
	var filter = /^([a-zA-Z0-9_.-])+@(([a-zA-Z0-9-])+.)+([a-zA-Z0-9]{2,4})+$/;
	if (!filter.test(email)) {
		alert("e-mail non corretta");
		return false;
	} else {
		return true;
	}
}