darcs patch: Fix #2005 [network package]

[Judah Jacobson]

The attached patch fixes Trac #2005 (getnameinfo error on mac with
ipv6 addresses).  The problem was caused by a failure to initialize
the field sockaddr_in6.sin6_len .  The initialization was only
happening on NetBSD; apparently OS X needs it too.

This patch sets that field if the macro SIN6_LEN is defined (which is
the standard way to detect that, according to my research online and
RFC 3493 (http://tools.ietf.org/html/rfc3493).

-Judah


Sat Jul 19 10:18:41 PDT 2008  Judah Jacobson <judah.jacobson at gmail.com>
  * FIX #2005: Set the sockaddr_in.sin6_len field on all platforms
that support it, not just NetBSD.

    M ./Network/Socket.hsc -1 +1