Hi,

On Thu, 02 Dec 2010 09:48:03 -0800, Dirk Hohndel <hohndel@infradead.org> wrote:
> On Wed,  1 Dec 2010 21:33:55 +0100, Joel Borggrén-Franck <joel.borggren.franck@gmail.com> wrote:
> > From: Joel Borggrén-Franck <jbf@codehouse.se>
> > 
> > Add headers cc: bcc: and to: to index. Real header to: is searched as
> > "exactto:foo@bar.baz" and search term "to:" is kept as a union of cc:,
> > bcc: and to: for backward compatibility. Use search term "cc:" resp.
> > "bcc:" to search those headers respectively.
> 
> cworth has been talking for a while about changing notmuch to index all
> of the headers - this is one of my key missing features at this point. 
> Searching for Sender: or X-Mailing-List: or (PLEASE!!!!) X-Spam-Score:

I second that ! I also need this feature (so sad I can't do it myself)