"It's a tough natural language processing task" It doesn't seem to be. For most part, it's the same e-mail headers that every other e-mail client uses to show

"It's a tough natural language processing task" It doesn't seem to be. For most part, it's the same e-mail headers that every other e-mail client uses to show threads: http://www.jwz.org/doc/threading.html http://www.jwz.org/doc/threading.html