function isValidMail(mail) {
    return /^[a-z0-9][a-z0-9_\.\-]*@[a-z0-9\.]+\.[a-z]{2,5}$/i.test(mail);
}

function isValidPostcode(postcode) {
    return /^[0-9]{2}\-[0-9]{3}$/i.test(postcode);
}
function isValidPhone(phone){
	return /^([0-9]){9,10}$/i.test(phone);
}