It is not a 100%-reproducible problem that seems to happen in several cases involving both an OUCS 7u4 and an old JCS 5 server (when exchanging messages between each other or even within a server bypassing any milters for example, or sending to other domains such as google, posting with web or SMTP-Auth).
The common thing is that the received attachment's headers lose the piece about character encoding of the first line of the filename:
--Boundary_(ID_aNbA9YOhlTUcvRNjPMb27Q)
Content-type: application/vnd.ms-excel;
name="0LPRgNCw0LzQvNGDINC+INC/0L7Rh9GC?=
=?UTF-8?B?0L7QstC+0Lkg0YHQuNGB0YLQtdC80LUg0LIg0KDQvtGB0L/QtdGH0LDRgtC4Lng=?=
=?UTF-8?B?bHM=?="
Content-transfer-encoding: base64
Content-disposition: attachment;
filename="0LPRgNCw0LzQvNGDINC+INC/0L7Rh9GC?= =?UTF-8?B?0L7QstC+0Lkg0YHQuNGB0YLQtdC80LUg0LIg0KDQvtGB0L/QtdGH0LDRgtC4Lng=?=
=?UTF-8?B?bHM=?=";
filename*0*=UTF-8''%D0%9E%D1%82%D0%B2%D0%B5%D1%82%20%D0%BD%D0%B0%20%D1%82;
filename*1*=%D0%B5%D0%BB%D0%B5%D0%B3%D1%80%D0%B0%D0%BC%D0%BC%D1%83%20%D0;
filename*2*=%BE%20%D0%BF%D0%BE%D1%87%D1%82%D0%BE%D0%B2%D0%BE%D0%B9%20%D1;
filename*3*=%81%D0%B8%D1%81%D1%82%D0%B5%D0%BC%D0%B5%20%D0%B2%20%D0%A0%D0;
filename*4*=%BE%D1%81%D0%BF%D0%B5%D1%87%D0%B0%D1%82%D0%B8%2E%78%6C%73
Sometimes messages do pass correctly, and in all cases they are saved into "Sent" folder correctly, so it is not a client error for example:
--------------090501050302010603060805
Content-Type: application/vnd.ms-excel;
name="=?UTF-8?B?0J7RgtCy0LXRgiDQvdCwINGC0LXQu9C10LPRgNCw0LzQvNGDINC+INC/0L7Rh9GC?=
=?UTF-8?B?0L7QstC+0Lkg0YHQuNGB0YLQtdC80LUg0LIg0KDQvtGB0L/QtdGH0LDRgtC4Lng=?=
=?UTF-8?B?bHM=?="
Content-Transfer-Encoding: base64
Content-Disposition: attachment;
filename*0*=UTF-8''%D0%9E%D1%82%D0%B2%D0%B5%D1%82%20%D0%BD%D0%B0%20%D1%82;
filename*1*=%D0%B5%D0%BB%D0%B5%D0%B3%D1%80%D0%B0%D0%BC%D0%BC%D1%83%20%D0;
filename*2*=%BE%20%D0%BF%D0%BE%D1%87%D1%82%D0%BE%D0%B2%D0%BE%D0%B9%20%D1;
filename*3*=%81%D0%B8%D1%81%D1%82%D0%B5%D0%BC%D0%B5%20%D0%B2%20%D0%A0%D0;
filename*4*=%BE%D1%81%D0%BF%D0%B5%D1%87%D0%B0%D1%82%D0%B8%2E%78%6C%73
As can be seen in this example, the boundary identifiers have changed (meaning IMHO that the message was processed - taken apart and put together again), and in this example only part of the first line makes it into the received message's filename header.
Another example:
"Sent":
--------------010609000006000200040201
Content-Type: application/pdf;
name="=?UTF-8?B?0YLQtdC70LXQs9GA0LDQvNC80LAg0L4g0YDQsNCx0L7RgtC1INGB0LjRgdGC0LXQvA==?=
=?UTF-8?B?0Ysg0L7QsdC80LXQvdCwINGN0LvQtdC60YLRgC4g0L/QvtGH0YLQvtCy0YvQvNC4?=
=?UTF-8?B?INGB0L7QvtCx0YnQtdC90LjRj9C80Lgg0L7RgiAxNC4xMC4xMy5wZGY=?="
"Received":
--Boundary_(ID_kv6CyB9foC+l8rLg7THT2g)
Content-type: application/pdf;
name="QsdC80LXQvdCwINGN0LvQtdC60YLRgC4g0L/QvtGH0YLQvtCy0YvQvNC4?=
=?UTF-8?B?INGB0L7QvtCx0YnQtdC90LjRj9C80Lgg0L7RgiAxNC4xMC4xMy5wZGY=?="
Since this happens both on a server with a spam/virus filters and on a server without any of those, and it is not 100% reproducible (though frequent) I can guess that sometimes messages pass through channels such as (de-)fragmentation, or Sieve, or something, and this breaks them.
Any ideas? Is this a misconfiguration or a CommSuite bug?
Thanks,
//Jim Klimov