** Posting articles and sending mail now has M-TAB completion on various<BR>
header fields (Newsgroups, To, CC, ...).
<P>
Completion in the Newsgroups header depends on the list of groups
known to your news reader.  Completion in the Followup-To header
offers those groups which are in the Newsgroups header, since
Followup-To usually just holds one of those.
<P>
Completion in fields that hold mail addresses works based on the list
of local users plus your aliases.  Additionally, if your site provides
a mail directory or a specific host to use for any unrecognized user
name, you can arrange to query that host for completion also.  (See the
documentation of variables `mail-directory-process' and
`mail-directory-stream'.)
<P>