> First, I am wondering about the mechanism that Listserv uses to keep
> track of the size of the digest (to determine when to send out a
> special edition). My hypothesis is that Listserv has an internal
> counter somewhere, and it counts the number of lines in an incoming
> message and adds that number to the counter. When the counter reaches
> the specified limit, it fires off the digest. Is my hypothesis
> correct?

No. LISTSERV checks the number of lines in the digest every time it
processes a new posting. There is no internal counter that could have gotten
corrupted.

Your log shows that LISTSERV is sending the digest. The 421 error you are
seeing comes from the SMTP workers and should be addressed, but is
unrelated. LISTSERV is happy as long as it is able to queue the mail for
later delivery. The SMTP workers are separate processes that work
asynchronously from the main LISTSERV process and report any errors to the
log as they occur, but do not feed any information back to LISTSERV. In a
nutshell, the digest process doesn't even know what problems the SMTP
workers may be encountering.

Your log suggests that the digest is sent successfully (forgetting the 421
error), but is then not reset. This can only happen if some kind of error
occurs in the digest posting process. I vaguely remember that in an earlier
version, I think it was 1.8c but it could have been 1.8d, there was a
condition where some types of errors in digest processing were not reported
to the log, so it may have looked like everything was ok, but in fact an
error did occur. If you have other lists, you will want to check if their
digests are working correctly. Either way, you should take a close look at
digests.file and eyeball listname.digest for anomalies. Sorry but I can't do
much more about a problem with 1.8d.

  Eric