On Tue, 11 Jun 1996 16:48:53 PDT, you said:
>         Does LISTSERV support the following feature: When an identical
> message is sent to multiple mailing lists, subscribers who belong to more
> than one of those lists receive only one copy of the message?
 
Well, this can be done (theoretically) for lists that are on the SAME HOST.
 
There's no general way to address this issue if you have 2 lists such as
[log in to unmask] and [log in to unmask]
 
>         I understand that differences in message formating (e.g. headers,
> footers) between lists may make implementing such a scheme problematic,
> but apparently Majordomo can be configured to do this.
 
Are you sure it's Majordomo, and not Sendmail or maybe even your MUA?  I know
that MH 6.8.4 and Procmail can both be configured to automagically suppress
duplicates based on the Message-ID: tag.  I would not be surprised to find that
other MUA's supported this too.  All that would be required is for the list
handling software to preserve the Message-ID: tag.
--
                                Valdis Kletnieks
                                Computer Systems Engineer
                                Virginia Tech