Bugzilla Bug 51721

ntpdate 4.2.0-r2 fails with the error "setsockopt() IPV6_V6ONLY failed:
Protocol not available".  IPv6 is enabled and operational on the box, and many
apps (apache, mozilla, ssh, etc.) work properly with it.  ntpdate uses an IPv4
time server address, and using the "-4" option with it has no effect on the
problem.

I have reverted to ntpdate 4.1.2 which doesn't have the problem.

# uname -a
Linux vishnu 2.4.20-gentoo-r9 #2 SMP Sun Feb 22 23:53:36 CST 2004 i686 Intel(R)
Pentium(R) 4 CPU 2.60GHz GenuineIntel GNU/Linux

# emerge info
Portage 2.0.50-r6 (default-x86-1.4, gcc-3.3.2, glibc-2.3.2-r9,
2.4.20-gentoo-r9)
=================================================================
System uname: 2.4.20-gentoo-r9 i686 Intel(R) Pentium(R) 4 CPU 2.60GHz
Gentoo Base System version 1.4.10
ccache version 2.3 [enabled]
Autoconf: sys-devel/autoconf-2.58-r1
Automake: sys-devel/automake-1.8.3
ACCEPT_KEYWORDS="x86"
AUTOCLEAN="yes"
CFLAGS="-O2 -mcpu=pentium4 -march=pentium4 -fprefetch-loop-arrays -pipe"
CHOST="i686-pc-linux-gnu"
COMPILER="gcc3"
CONFIG_PROTECT="/etc /usr/X11R6/lib/X11/xkb /usr/kde/2/share/config
/usr/kde/3.1/share/config /usr/kde/3.2/share/config /usr/kde/3/share/config
/usr/lib/mozilla/defaults/pref /usr/share/config
/usr/share/texmf/dvipdfm/config/ /usr/share/texmf/dvips/config/
/usr/share/texmf/tex/generic/config/ /usr/share/texmf/tex/platex/config/
/usr/share/texmf/xdvi/ /var/qmail/control"
CONFIG_PROTECT_MASK="/etc/gconf /etc/terminfo /etc/env.d"
CXXFLAGS="-O2 -mcpu=pentium4 -march=pentium4 -fprefetch-loop-arrays -pipe"
DISTDIR="/usr/portage/distfiles"
FEATURES="autoaddcvs ccache sandbox"
GENTOO_MIRRORS="ftp://gentoo.noved.org/ http://gentoo.noved.org/
ftp://ftp.ussg.iu.edu/pub/linux/gentoo"
MAKEOPTS="-j3"
PKGDIR="/usr/portage/packages"
PORTAGE_TMPDIR="/var/tmp"
PORTDIR="/usr/portage"
PORTDIR_OVERLAY="/usr/local/portage"
SYNC="rsync://rsync.gentoo.org/gentoo-portage"
USE="X Xaw3d acl acpi alsa apache2 apm arts avi berkdb bindist bonobo cdr crypt
cups curl doc dvd dvdr encode esd evo fastcgi flash foomaticdb gdbm gif gnome
gpm gps gstreamer gtk gtk2 gtkhtml guile imap imlib ipv6 java jikes jpeg libg++
libwww mad maildir mcal mikmod motif mozilla mpeg mysql ncurses nls oggvorbis
opengl oss pam pdflib perl plotutils png ppds python quicktime readline samba
sasl scanner sdl slang slp snmp spell sse ssl svga tcltk tcpd tetex tiff
truetype usb x86 xml xml2 xmms xosd xv zeo zlib"

I should add that there's been some discussion of this on the gentoo forums,
and I'm apparently not alone with this problem.  see

http://forums.gentoo.org/viewtopic.php?t=156776

4.2.0.20040617 has a bunch of ipv6 fixes