Log Message:
Update of mail/nail to 10.4. Changes since 10.3 (as per e-mail
from Gunnar Ritter):

* A missing #ifdef HAVE_ICONV caused build errors on platforms without
  iconv() support (J.A. Neitzel, Jens Schleusener, Lars Kellogg-Stedman,
  Felicia Neff, Chris Pinnock).
* Extraction of parts from header fields with more than 2560 characters
  fixed (Lukasz Sznuk, William Cherry).
* Source archive name in nail.spec corrected (Didar Hussain).
* Fixed segmentation violation when encountering multipart header fields
  that contain no ':' character (William Cherry).
* Respect the 'allnet' variable when comparing strings in message lists.
* IPv6 support (Jun-ichiro itojun Hagino).