Working with or without javascript it’s combine two technique for email protection ROT13 and CSS
function mail($email, $text = null) { return '<script type="text/javascript">document.write("' . addslashes( str_rot13( '<a href="mailto:' . $email . '" rel="nofollow">' . ($text ? : $email) . '</a>' ) ) . '".replace(/[a-zA-Z]/g,function(c){return String.fromCharCode((c<="Z"?90:122)>=(c=c.charCodeAt(0)+13)?c:c-26);}));</script>' . '<noscript><span style="unicode-bidi: bidi-override; direction: rtl;">' . strrev($email) . '</span></noscript>';}