Sorry, very last mail from me on this issue. I squashed the patches into 3 distinct ones, and inherited a tree from cworth's master tree for easier pulling (rather than basing it off my all-features branch). This branch is here:
http://github.com/spaetz/notmuch-all-feature/commits/dateparser2 (git://github.com/spaetz/notmuch-all-feature.git then switch to branch 'dateparser2')