On Sun, 25 Feb 2001 14:18:22 +0200, Erwin Weiblen <[log in to unmask]>
wrote:

>> >e.g. by inserting a header line "X-Number: ..." ?
>
>> There is no such header line so this won't work.
>
>Where are the possible "X-..."-headers listed?

Sorry.  I was thinking you meant List Header, in which case there is currently
no such Keyword.  In RFC822 Mail Headers you can make almost any header line you
want that begins with X-...  so this could be done in the mail headers.
However, LISTSERV would have to be modified to write this line (and a List
Header setting of some kind would have to be implemented to control this
feature, etc...)  I'll put your comments in the suggestion box.