On Mon, Sep 20, 2010 at 03:38:16PM +0200, mjsseppl-m...@yahoo.de wrote: > On 10.09.20, mjsseppl-m...@yahoo.de wrote: > > On 10.09.20, Yue Wu wrote: > > > Do "H" and look at the headers and you'll see under References: > > <20100919012315.gc36...@fbsd.t60.cpu> <20100919071840.ga26...@murdoc> > > etc. > > > > "In-Reply-To:" is also used.
"In-Reply-To:" is standard, while "References:" is a Usenet-ism. Good MUAs will thread based on both. Some MUAs break threading (by including neither of those two headers), so sometimes it's necessary to match replies via subject matching. Mutt supports all of this, and uses asterisks to mark mails which break threading. (MUAs could go so far as to match quoting in mail bodies, but that's really hard.) See: http://www.jwz.org/doc/threading.html Nico --
