Exim 4.88 has some Known Issues and we're in the late stages of Release
Candidate testing for Exim 4.89. (I'm going to cut RC7 tonight). Exim
4.89 will be a stabilization release.
In the meantime, if using Exim 4.88, please disable all use of the
CHUNKING extension. There are various known problems which can result
in messages stuck in queues and remote servers dropping connections on
larger mails.
If you're considering deploying Exim 4.88, please deploy the Release
Candidate instead, it's already much better. If you're deploying a
pre-built binary of 4.88, then in the main configuration section add:
# Work-around for 4.88 bugs:
chunking_advertise_hosts =
and in each SMTP Transport, add:
# Work-around for 4.88 bugs:
hosts_try_chunking =
Thanks for your understanding and patience,
-Phil Pennock, pp The Exim Maintainers
