function checkPhoneNumber(field) {
	var fel=document.getElementById(field);
	var phone=fel.value;
	var phoneout='';
	for (var i=0; i<phone.length; i++) {
		if (phone.charAt(i)>='0' && phone.charAt(i)<='9') {
			phoneout+=phone.charAt(i);
		}
	}
	if (phoneout.length>7) {
		phoneout='('+phoneout.substring(0,3)+')'+phoneout.substring(3,6)+'-'+phoneout.substring(6);
	} else if (phoneout.length>3) {
		phoneout=phoneout.substring(0,3)+'-'+phoneout.substring(3);
	}
	fel.value=phoneout;
}