sendmail_path = /usr/sbin/sendmail -f yourname@sth.com -t -i

mail($to, $subject, $content, $headers);

修改 $subject = "=?UTF-8?B?".base64_encode(标题)."?=";

$headers = 'Content-type: text/html; charset=utf-8' . "\r\n";

        $to =  a@b.com,b@b.com;

        $headers = 'Content-type: text/html; charset=utf-8' . "\r\n"; // 其他 from  之类的head也可以从这里配置

        $subject = "=?UTF-8?B?".base64_encode('测试邮件')."?=";

        mail($to, $subject, $content, $headers);      

set encoding=utf-8

set fileencoding=utf-8