Corbett, i've been hoping to find a minute to look into this behavior - i may be able to get to it later today. In the meanwhile, please check for any relevant entries in your ~mailman/logs/errors log file, and if there are any, send copies to me.
And let me see if i understand correctly - you say that /var/log/maillog indicates that your sendmail sent the messages to the users, but the users never see them? This would suggest that the messages *really* foul up the receiving side - and that brings one possibilty to mind.
There is a known bug in some recent versions of sendmail (8.8.x for some x, and 8.9.0) such that the sendmail will core dump when attempting to deliver mailman's (or any 8-bit encoded) Mime-format digests in certain (somewhat uncommon) circumstances. The question then is, were the messages that never appeared in the users mailbox Mime digests? And if not, could you construct a repeatable test that at least reduces the likelihood that the problem is on the receiving ends? For that matter, might you happen to be running sendmail 8.8.x or 8.9.0? Your sendmail may be getting so far as negotiating the delivery and then failing partway through...
With the info available currently it's hard to know what of mailman to investigate on this end, since mailman evidently got the messages to your MTA.
Ken Manheimer klm@python.org 703 620-8990 x268 (orporation for National Research |nitiatives
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