diff -aurN --exclude '*~' --exclude configure --exclude aclocal.m4 --exclude config.h.in --exclude '*rej' --exclude '*orig' cyrus-imapd-2.0.15.orig/cmulocal/ipv6.m4 cyrus-imapd-2.0.15/cmulocal/ipv6.m4
--- cyrus-imapd-2.0.15.orig/cmulocal/ipv6.m4	Thu Jan  1 01:00:00 1970
+++ cyrus-imapd-2.0.15/cmulocal/ipv6.m4	Tue Jul 10 08:19:03 2001
@@ -0,0 +1,68 @@
+dnl See whether we can use IPv6 related functions
+AC_DEFUN(IPv6_CHECK_FUNC, [
+changequote(, )dnl
+ac_tr_lib=HAVE_`echo $1 | sed -e 's/[^a-zA-Z0-9_]/_/g' \
+  -e 'y/abcdefghijklmnopqrstuvwxyz/ABCDEFGHIJKLMNOPQRSTUVWXYZ/'`
+changequote([, ])dnl
+AC_CHECK_FUNC($1, [dnl
+  AC_DEFINE_UNQUOTED($ac_tr_lib)
+  ac_cv_lib_socket_$1=no
+  ac_cv_lib_inet6_$1=no
+], [dnl
+  AC_CHECK_LIB(socket, $1, [dnl
+    AC_DEFINE_UNQUOTED($ac_tr_lib)
+    LIBS="$LIBS -lsocket"
+    ac_cv_lib_inet6_$1=no
+  ], [dnl
+    AC_MSG_CHECKING([whether your system has IPv6 directory])
+    AC_CACHE_VAL(ipv6_cv_dir, [dnl
+      for ipv6_cv_dir in /usr/local/v6 /usr/inet6 no; do
+	if test $ipv6_cv_dir = no -o -d $ipv6_cv_dir; then
+	  break
+	fi
+      done])dnl
+    AC_MSG_RESULT($ipv6_cv_dir)
+    if test $ipv6_cv_dir = no; then
+      ac_cv_lib_inet6_$1=no
+    else
+      if test x$ipv6_libinet6 = x; then
+	ipv6_libinet6=no
+	SAVELDFLAGS="$LDFLAGS"
+	LDFLAGS="$LDFLAGS -L$ipv6_cv_dir/lib"
+      fi
+      AC_CHECK_LIB(inet6, $1, [dnl
+	AC_DEFINE_UNQUOTED($ac_tr_lib)
+	if test $ipv6_libinet6 = no; then
+	  ipv6_libinet6=yes
+	  LIBS="$LIBS -linet6"
+	fi],)dnl
+      if test $ipv6_libinet6 = no; then
+	LDFLAGS="$SAVELDFLAGS"
+      fi
+    fi])dnl
+])dnl
+if test $ac_cv_func_$1 = yes -o $ac_cv_lib_socket_$1 = yes \
+     -o $ac_cv_lib_inet6_$1 = yes
+then
+  ipv6_cv_$1=yes
+  ifelse([$2], , :, [$2])
+else
+  ipv6_cv_$1=no
+  ifelse([$3], , :, [$3])
+fi])
+
+dnl See whether we have ss_family in sockaddr_storage
+AC_DEFUN(IPv6_CHECK_SS_FAMILY, [
+AC_MSG_CHECKING([whether you have ss_family in struct sockaddr_storage])
+AC_CACHE_VAL(ipv6_cv_ss_family, [dnl
+AC_TRY_COMPILE([#include <sys/types.h>
+#include <sys/socket.h>],
+	[struct sockaddr_storage ss; int i = ss.ss_family;],
+	[ipv6_cv_ss_family=yes], [ipv6_cv_ss_family=no])])dnl
+if test $ipv6_cv_ss_family = yes; then
+  ifelse([$1], , AC_DEFINE(HAVE_SS_FAMILY), [$1])
+else
+  ifelse([$2], , :, [$2])
+fi
+AC_MSG_RESULT($ipv6_cv_ss_family)])
+