These are probably encoded MIME messages. The people who designed MIME made the strategic decision, after a long debate, that MIME would be a MUA-only (or MUA-mostly) issue and that no modification would be required to MTA's for MIME, with the possible exception of gateways. This means it is the user sending the message who decides whether or not recipients can handle MIME. In the case of a mailing list, it is very unlikely that all subscribers will have MIME user interfaces, so you have a choice between not using MIME and sending rubbish to some of the subscribers. LISTSERV can't take the responsibility of decoding the message for the user, especially as it can only decode certain types of MIME messages. There is little or nothing LISTSERV can do about audio tracks, multi-part messages and the like. The only case which is simple to handle is a plain single-part text message where the contents have been encoded to pass through some 7-bit mailer. Eric