- IPv6 workarounds from Hideaki YOSHIFUJI <yoshfuji@ecei.tohoku.ac.jp>
diff --git a/configure.in b/configure.in
index 90aadd9..4f1e479 100644
--- a/configure.in
+++ b/configure.in
@@ -55,6 +55,8 @@
 	;;
 *-*-linux*)
 	no_dev_ptmx=1
+	AC_DEFINE(DONT_TRY_OTHER_AF)
+	inet6_default_4in6=yes
 	;;
 *-*-netbsd*)
 	need_dash_r=1
@@ -788,6 +790,26 @@
 	]
 )
 
+AC_MSG_CHECKING([to convert IPv4 in IPv6-mapped addresses])
+AC_ARG_WITH(4in6,
+	[  --with-4in6             Check for and convert IPv4 in IPv6 mapped addresses],
+	[
+		if test "x$withval" != "xno" ; then
+			AC_MSG_RESULT(yes)
+			AC_DEFINE(IPV4_IN_IPV6)
+		else
+			AC_MSG_RESULT(no)
+		fi
+	],[
+		if test "x$inet6_default_4in6" = "xyes"; then
+			AC_MSG_RESULT([yes (default)])
+			AC_DEFINE(IPV4_IN_IPV6)
+		else
+			AC_MSG_RESULT([no (default)])
+		fi
+	]
+)
+
 # Where to place sshd.pid
 piddir=/var/run
 AC_ARG_WITH(pid-dir,