To sum up, the problem occurs at seemingly random times (but often), when running vdelivermail from the Maildrop filter file. As Matt described, the error as it appears in the qmail-send log looks like:
2005-02-18 21:58:22.285783500 delivery 181: deferral: Sorry,_no_mailbox_here_by_that_name._vpopmail_(#5.1.1)/maildrop: _error_writing_to_mailbox./
Clearly this should be a bounce aka failure, not a deferral, but maildrop determines there is a problem when calling vdelivermail, so it returns with exitcode 75 which causes the deferral.
I believe the source of this problem was identifed back in June by someone posting to the Maildrop mailing list, although there were no responses. See:
To sum up again, he says the problem "is because vdelivermail exits, before it read the pipe completly. vdelivermail simply checks whether the receipient is valid, and if not,
exits at once, causing a SIGPIPE in maildrop."
It should be possible to update vdelivermail to scan through to the end of the message before exiting. It might add some additional overhead, but I think that it would avoid the SIGPIPE.
Tom Collins - [EMAIL PROTECTED]
QmailAdmin: http://qmailadmin.sf.net/ Vpopmail: http://vpopmail.sf.net/
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