function isSignEmailAddress (string) {
	var addressPattern = /^\w+((-\w+)|(\.\w+))*\@[A-Za-z0-9]+((\.|-)[A-Za-z0-9]+)*\.[A-Za-z0-9]+$/;
	return addressPattern.test(string);
}
function validateSignup(f) {
	var err ="";
	if (isSignEmailAddress(f.email.value)==false) {
		err+="Your Email is invalid"+"\r\n";
	} 
	if (err!="") { 
		alert(err);
		return false;
	} else {
            f.required.value="1";
            return true;
        }
}