function valid_email(e){ 
  if (e.match(/^[A-Za-z0-9_\+-]+(\.[A-Za-z0-9_\+-]+)*@[A-Za-z0-9-]+(\.[A-Za-z0-9-]+)*\.([A-Za-z]{2,4})$/)) { 
   return true; 
  } else {
   return false;
  }
} 	

function subscribe_me(f) { 
	if (! valid_email(f.email.value)) { 
		alert('Please enter a valid email address. For example: "sgtpepper@heartsclubband.com"'); 
		return false; 
	} else { 
		return true; 
	} 
}