For individual e-mail distribution (non-moderated),
no support for it in the subject: field.
 
DIGEST or INDEX distribution would place the listname
in the Subject:.  Here's an example of an INDEXed distribution:
 
Date:     Fri, 1 Dec 1995 15:00:16 -0500
Reply-To: [log in to unmask]
X-Sender:   Computer-assisted Reporting & Research <[log in to unmask]>
From:     Automatic digest processor <[log in to unmask]>
Subject:  CARR-L Index - 30 Nov 1995 to 1 Dec 1995
X-To:       Recipients of CARR-L indexes <[log in to unmask]>
 
--  co-owner INFOSYS, TQM-L, CPARK-L, ERAPPA-L, JANITORS, LDBASE-L, et -L
URL:mailto:[log in to unmask]               "IRA professional list-owner"
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