See https://bazaar.launchpad.net/~mailman- coders/mailman/2.1/revision/1813 The reason this broke on your server change was Debian's misguided changing of Mailman's character set for all languages to UTF-8. See https://bugs.launchpad.net/mailman/+bug/1462755 ** Changed in: mailman Importance: Undecided => Low ** Changed in: mailman Status: Incomplete => Fix Committed ** Changed in: mailman Milestone: None => 2.1.30 -- You received this bug notification because you are a member of Mailman Coders, which is subscribed to GNU Mailman. https://bugs.launchpad.net/bugs/1831321 Title: the List-Id field is filled without < and > around the list-id if the description contains unsupported characters To manage notifications about this bug go to: https://bugs.launchpad.net/mailman/+bug/1831321/+subscriptions