When I said "less strict" I ment is it possible to have an attachment to
the orginial subject heading like: "RE:" or "Ex:". After the attachment,
the orginial subject heading would follow. See, I need my people to read
the mails on the page and then send attachments separately from the mails.
It is similar to replying to the mails without actually pressing the
"reply button" while reading the individual mail.
I still have problems on how this relates to mhonarc, or what you are
asking. A guess is you want messages with "re:" to be considered a
separate thread from the original message (but this cannot be right).
Mhonarc ignores "re:" in subjects when performing threading.
If you are talking about messages that come from a CGI form, than
the CGI form should prepend the "re:" to the subject.