- mb_decode_mimeheader: documentation ( source)
- mb_encode_mimeheader: documentation ( source)
- mb_internal_encoding: documentation ( source)
<?php
mb_internal_encoding('ISO-8859-1');
echo 'Subject: ', mb_decode_mimeheader('=?ISO-8859-1?B?0JTQvtCx0LDQstC70LXQvSDQvdC+0LLRi9C5INC60L4=?=
=?ISO-8859-1?B?0LzQvNC10L3RgtCw0YDQuNC5INC6INCy0L7Qv9GA0L7RgdGDINA=?=
=?ISO-8859-1?B?vdCwIENyZWRpdENhcmRzT25saW5lLnJ1?=');
$name = 'Новый вопрос на сайте ff.ru';
$addr = mb_encode_mimeheader($name, "ISO-8859-1", "B");
echo $addr;