Log username MTA option

Transaction logging MTA options:  (0-511)
The  MTA option is a bit-encoded value which controls whether or not user information associated  with a process that enqueues mail is saved in the   file  (and optional   file) or included in    mapping probes.

Note that messages submitted via SMTP with authentication (SMTP AUTH) will be considered to be owned by the username that authenticated, prefixed with the asterisk,, character. (Note also that messages enqueued to the   channel always get the enqueueing username set to literally   ; this is for access control purposes.)

The bits in the  option are described in the following table:

Bit 0 is the least significant bit.

As of MS 6.3p1, enabling XML or JSON format (  set to 4 or 5, respectively) causes the default for   to be 1; with any other format, the default is 0, as was always the case in previous versions.

See also:
 * Transaction logging MTA options
 * MTA transaction logging
 * log_format MTA Option
 * Triggering effects from transaction logging with LOG_ACTION
 * log_message_id MTA Option
 * log_connection MTA Option