function validate_formab(frm)
 {
  if (!check_empty(frm.name.value))
  	{ 
	alert('You have not entered a name!'); 
	return false;
	}
  if (!check_email(frm.Email.value))
  	{
	alert('You have entered an invalid Email address!'); 
	return false; 
	}
  if (!check_empty(frm.phone.value))
  	{ 
	alert('You have not entered a phone number!'); 
	return false; 
	}
} 

function check_empty(text) {
  return (text.length > 0); // returns false if empty
}

function check_email(address) {
  if ((address == "")
    || (address.indexOf ('@') == -1)
    || (address.indexOf ('.') == -1))
      return false;
  return true;
}