[Mailman-Users] Special characters in the subject line deleted

[Malte Gersch]

Hi all,

we are using mailman 2.1.12 and postfix on our own server and we are currently having some issues with special characters in the "subject" line.

When I send a mail with the test subject "Umlauteäuüö" to a list, procmail delivers the mail to mailman with the header line "Subject: =?iso-8859-1?B?VW1sYXV0ZeR1/PY=?=". 

The mail from mailman to the list-subscribers has the subject "[Testlisteäü]Umlauteu". i.e. the special characters are missing and the space after "]" is missing, too. The header line is "Subject: =?utf-8?b?W1Rlc3RsaXN0ZcOkw7xd?= =?iso-8859-1?q?Umlaute=E4u=FC=F6?="

Does anybody have ideas where this could come from?

Thanks!
Malte