Saving sent mail to same group

[Jean-Louis Leroy <jll@soundobjectlogic.com>]

Hello,

I'd like Gnus to archive sent mail to the group in which the mail was
created (or to nnfolder+archive:sent-mail if the message was created
directly in the *Group* buffer).

The purpose is to make messages sent to a thread appear right in that
thread; also, when I create a message while sitting a a group's
summary buffer, I'd like the archive to go there.

To make things clear, let's suppose I enter group
nnml+private:mail.foo and hit 'm'. I compose the message and send
it. The archived message goes into nnml+private:mail.foo. The
message's recipient replies and my split method directs his reply to
nnml+private:mail.foo; I reply to his reply and once again the archive
goes to nnml+private:mail.foo. So when I do a Thread Show in
nnml+private:mail.foo, I see both my messages and the reply properly
threaded.

Is that feasible? Thanks.
-- 
Jean-Louis Leroy
Sound Object Logic
http://www.soundobjectlogic.com