Some possibly useful information: I have Claws-mail 2.8.1-3 running on an N770 with the 2006 OS (specifically 2.2006.39-14). I downloaded it from https://garage.maemo.org/projects/claws-mail, then tried to install it using "Install from file" in the Application Manager's menu. Result: a message saying it couldn't install because it needed libsm6. I then opened an xterm, did "apt-get install libsm6", and again tried installing. Success! Double tapping on a message won't open it, but selecting it with a tap and then pressing the center button in the scroll pad on the left does. Also helpful: the info about icons under Help, the manual and FAQ at www.claws-mail.org, and the info in this thread (esp. about IMAP folders). A great app, infinitely better than the default email client.