Support for SMTP chunking (RFC 3030) has been added to both the SMTP client and server. This support is enabled by default. Four new channel keywords can be used to control whether or not chunking is allowed. They are as follows:
chunkingclient - Enable client chunking support (default).
chunkingserver - Enable server chunking support (default).
nochunkingclient - Disable client chunking support.
nochunkingserver - Disable server chunking support.
The log file action field has been extended to indicate whether or not chunking was used to transfer a given message. Specifically, a C will be appended if chunking is used. Note that ESMTP has to be used for chunking to work, so you'll typically see field values like EEC or DEC.