On Mon, 31 Jul 2006 09:40:12 -0500, Hal Keen <[log in to unmask]> wrote:

>>   Subject: Cat: This message is about cats
>>   (valid syntax, but CAT is not a topic, will go to ALL and OTHER)
>
>I had understood that the ALL topic must be specified, and that messages
>with no recognized topic went only to OTHER.
>
>Can this be clarified?

You are correct.  Messages with no recognized topic go only to OTHER.

I was thinking that persons subscribed to ALL topics would also include the
OTHER topic, but it is possible to be subscribed as  "+ALL -OTHER" which would
include all listed topics but not the OTHER topic.  In such case, you would
not get a message classified as OTHER.  

Yes, if you want to send a message to everyone set to any combination of the
listed topics for your list, you must specify ALL: at the beginning of the
Subject: line.  Continuing in the example stated before:

 Subject: ALL: This message is about all animals
 (This message will go to anyone subscribed to topics bird, dog, or frog. It
will also go to persons subscribed to the OTHER topic, since OTHER is part of
ALL.)  

I assume (but have not tested) that the above message will not go to anyone
not subscribed to any topics.  This is why you should define some
Default-Topics so new subscribers will automatically be assigned to some
topic(s).  Of course if Topics are required for your list, then a subscriber
who is not subscribed to any topics is not going to get much mail.  This is a
human issue, not a technical LISTSERV matter.