o Minor bugfixes:
    - When running with an older Linux kernel that erroneously responds
      to strange nmap behavior by having accept() return successfully
      with a zero-length socket, just close the connection. Previously,
      we would try harder to learn the remote address: but there was no
      such remote address to learn, and our method for trying to learn
      it was incorrect. Fixes bugs #1240, #4745, and #4747. Bugfix on
      0.1.0.3-rc. Reported and diagnosed by "r1eo".