IMTA_LANG:return_option.dat (DSN)IMTA_LANG:disposition_option.dat (MDN)

DAY (DSN)

The text to insert for a %U or %u substitution when RETURN_UNITS=0 (the default) is set. Note that no distinction is made between %U and %u (unlike the default case where English “Day” or “day”, respectively, would be substituted).

DIAGNOSTIC_CODE (DSN)

Override for the “Diagnostic code:“ text used in the construction of the per-recipient section of the first part of a DSN. This field should be specified in the same charset that’s used for the first part of the DSN.

HOUR (DSN)

The text to insert for a %U or %u substitution when RETURN_UNITS=1 is set. Note that no distinction is made between %U and %u (unlike the default case where English “Hour” or “hour”, respectively, would be substituted).

n.n.n (DSN)

When constructing the per-recipient part of a DSN a check will be made to see if there’s an option whose name matches the numeric per-recipient status. If there is the corresponding text will be inserted into the DSN. Additionally, if the REASON option specified above produces a zero length result the REASON field will not be inserted.

ORIGINAL_ADDRESS (DSN)

Override for the “Original address:” text used in the construction of the per-recipient section of the first part of a DSN. This field should be specified in the same charset that’s used for the first part of the DSN. 

REASON (DSN)

Override for the “Reason:” text used in the construction of the per-recipient section of the first part of a DSN. This field should be specified in the same charset that’s used for the first part of the DSN.

RECIPIENT_ADDRESS (DSN)

Override for the “Recipient address:” text used in the construction of the per-recipient section of the first part of a DSN. This field should be specified in the same charset that’s used for the first part of the DSN. 

RETURN_PERSONAL (DSN and MDN)

Override personal name field to be used in conjunction with the From: field. This field should be RFC 2047 encoded. The value set by the RETURN_PERSONAL MTA option is used if this option is not specified.

SUBJECT (DSN and MDN)

Override Subject: field. This value will only be used if the notification didn’t provide a subject field of its own. This field should be RFC 2047 encoded. An appropriate subject will be constructed if this option isn’t used and the notification didn’t provide one. 

TEXT_CHARSET (MDN)

Charset text for the first part and subject of the MDN should be converted to. The default is not to perform any conversion.