/SUBADDRESS=subaddress

    Specify a subaddress to attach to the envelope From: address;
    e.g., if the envelope From: address is prospero@example.com then
    specifying /SUBADDRESS="Postmaster" would result in the envelope
    From: address prospero+Postmaster@example.com.

    The /SUBADDRESS qualifier has no effect on interactive PMDF MAIL
    sessions.