PHP mail special characters in subject field

Question

I would like to insert special characters in the subject of HTML e-mails sent with the PHP mail() function.

I want my subject to look like this:

★ Yo

Answer 1

Try for subject:

$sub = '=?UTF-8?B?'.base64_encode($subject).'?=';

And then:

mail($to, $sub, $message, $headers);