MIME support in V8 sendmail has been coupled to ESMTP of the new BODY parameter for the MAIL FROM: command. That parameter tells sendmail whether it is dealing with 7-bit or 8-bit MIME data:^[15]

^[15] BODY=BINARYMIME might be an option in the future.

MAIL From:<address> BODY=7BIT
MAIL From:<address> BODY=8BITMIME

The parameter specified for the BODY (BIT or BITMIME) is the value stored in the ${bodytype} macro.

The ${bodytype} macro is intended to be used as part of the delivery agent's A= equate (A=). It provides a means to pass this information to delivery agent programs as part of their command lines.

${bodytype} is transient. If defined in the configuration file or in the command line, that definition can be ignored by sendmail. Note that the -B command-line switch (-B) can be used to specify a value to be stored in ${bodytype}, but only for initial mail submission. Also note that a $& prefix is necessary when you reference this macro in rules (that is, use $&{bodytype}, not ${bodytype}).