I just tried sending an email to both wikien-l and wikimediauk-l (both addresses in the From: line). I then got a message back saying the message was in the moderation queue because "Message has implicit destination". I'm a moderator on wikien-l, so I looked at the message and it had no subject and no body. Huh?
Sending a message to wikien-l on its own worked fine ...
- d.