diff --git a/configure b/configure
index bb163da927..75844461b2 100755
--- a/configure
+++ b/configure
@@ -1,6 +1,6 @@
 #! /bin/sh
 
-# From configure.in Revision: 1.50 
+# From configure.in Revision: 1.51 
 
 
 
@@ -2058,18 +2058,6 @@ case "$host" in
 	*-dec-osf*)
 				cat >> confdefs.h <<\EOF
 #define _SOCKADDR_LEN 1
-EOF
-
-		;;
-	*-sun-solaris*)
-				cat >> confdefs.h <<\EOF
-#define NEED_XPG4_2_BEFORE_SOCKET_H 1
-EOF
-
-		;;
-	*-hp-hpux*)
-				cat >> confdefs.h <<\EOF
-#define NEED_XSE_BEFORE_SOCKET_H 1
 EOF
 
 		;;
@@ -2077,9 +2065,9 @@ esac
 
 
 echo $ac_n "checking for sa_len in struct sockaddr""... $ac_c" 1>&6
-echo "configure:2081: checking for sa_len in struct sockaddr" >&5
+echo "configure:2069: checking for sa_len in struct sockaddr" >&5
 cat > conftest.$ac_ext <<EOF
-#line 2083 "configure"
+#line 2071 "configure"
 #include "confdefs.h"
 
 #include <sys/types.h>
@@ -2088,7 +2076,7 @@ int main() {
 struct sockaddr sa; sa.sa_len = 0; return (0);
 ; return 0; }
 EOF
-if { (eval echo configure:2092: \"$ac_compile\") 1>&5; (eval $ac_compile) 2>&5; }; then
+if { (eval echo configure:2080: \"$ac_compile\") 1>&5; (eval $ac_compile) 2>&5; }; then
   rm -rf conftest*
   echo "$ac_t""yes" 1>&6
 	ISC_NET_HAVESALEN="#define ISC_NET_HAVESALEN 1"
@@ -2103,10 +2091,37 @@ rm -f conftest*
 
 
 
-echo $ac_n "checking for interface list sysctl""... $ac_c" 1>&6
-echo "configure:2108: checking for interface list sysctl" >&5
+echo $ac_n "checking for struct msghdr flavor""... $ac_c" 1>&6
+echo "configure:2096: checking for struct msghdr flavor" >&5
 cat > conftest.$ac_ext <<EOF
-#line 2110 "configure"
+#line 2098 "configure"
+#include "confdefs.h"
+
+#include <sys/types.h>
+#include <sys/socket.h>
+int main() {
+struct msghdr msg; msg.msg_flags = 0; return (0);
+; return 0; }
+EOF
+if { (eval echo configure:2107: \"$ac_compile\") 1>&5; (eval $ac_compile) 2>&5; }; then
+  rm -rf conftest*
+  echo "$ac_t""4.4BSD" 1>&6
+	ISC_NET_MSGHDRFLAVOR="#define ISC_NET_BSD44MSGHDR 1"
+else
+  echo "configure: failed program was:" >&5
+  cat conftest.$ac_ext >&5
+  rm -rf conftest*
+  echo "$ac_t""4.3BSD" 1>&6
+	ISC_NET_MSGHDRFLAVOR="#define ISC_NET_BSD43MSGHDR 1"
+fi
+rm -f conftest*
+
+
+
+echo $ac_n "checking for interface list sysctl""... $ac_c" 1>&6
+echo "configure:2123: checking for interface list sysctl" >&5
+cat > conftest.$ac_ext <<EOF
+#line 2125 "configure"
 #include "confdefs.h"
 
 #include <sys/param.h>
@@ -2213,7 +2228,7 @@ else
 fi
 
 echo $ac_n "checking build system type""... $ac_c" 1>&6
-echo "configure:2217: checking build system type" >&5
+echo "configure:2232: checking build system type" >&5
 
 build_alias=$build
 case "$build_alias" in
@@ -2242,7 +2257,7 @@ ac_prog=ld
 if test "$ac_cv_prog_gcc" = yes; then
   # Check if gcc -print-prog-name=ld gives a path.
   echo $ac_n "checking for ld used by GCC""... $ac_c" 1>&6
-echo "configure:2246: checking for ld used by GCC" >&5
+echo "configure:2261: checking for ld used by GCC" >&5
   ac_prog=`($CC -print-prog-name=ld) 2>&5`
   case "$ac_prog" in
     # Accept absolute paths.
@@ -2266,10 +2281,10 @@ echo "configure:2246: checking for ld used by GCC" >&5
   esac
 elif test "$with_gnu_ld" = yes; then
   echo $ac_n "checking for GNU ld""... $ac_c" 1>&6
-echo "configure:2270: checking for GNU ld" >&5
+echo "configure:2285: checking for GNU ld" >&5
 else
   echo $ac_n "checking for non-GNU ld""... $ac_c" 1>&6
-echo "configure:2273: checking for non-GNU ld" >&5
+echo "configure:2288: checking for non-GNU ld" >&5
 fi
 if eval "test \"`echo '$''{'ac_cv_path_LD'+set}'`\" = set"; then
   echo $ac_n "(cached) $ac_c" 1>&6
@@ -2305,7 +2320,7 @@ fi
 test -z "$LD" && { echo "configure: error: no acceptable ld found in \$PATH" 1>&2; exit 1; }
 
 echo $ac_n "checking if the linker ($LD) is GNU ld""... $ac_c" 1>&6
-echo "configure:2309: checking if the linker ($LD) is GNU ld" >&5
+echo "configure:2324: checking if the linker ($LD) is GNU ld" >&5
 if eval "test \"`echo '$''{'ac_cv_prog_gnu_ld'+set}'`\" = set"; then
   echo $ac_n "(cached) $ac_c" 1>&6
 else
@@ -2321,7 +2336,7 @@ echo "$ac_t""$ac_cv_prog_gnu_ld" 1>&6
 
 
 echo $ac_n "checking for BSD-compatible nm""... $ac_c" 1>&6
-echo "configure:2325: checking for BSD-compatible nm" >&5
+echo "configure:2340: checking for BSD-compatible nm" >&5
 if eval "test \"`echo '$''{'ac_cv_path_NM'+set}'`\" = set"; then
   echo $ac_n "(cached) $ac_c" 1>&6
 else
@@ -2358,7 +2373,7 @@ echo "$ac_t""$NM" 1>&6
 
 
 echo $ac_n "checking whether ln -s works""... $ac_c" 1>&6
-echo "configure:2362: checking whether ln -s works" >&5
+echo "configure:2377: checking whether ln -s works" >&5
 if eval "test \"`echo '$''{'ac_cv_prog_LN_S'+set}'`\" = set"; then
   echo $ac_n "(cached) $ac_c" 1>&6
 else
@@ -2402,8 +2417,8 @@ test x"$silent" = xyes && libtool_flags="$libtool_flags --silent"
 case "$host" in
 *-*-irix6*)
   # Find out which ABI we are using.
-  echo '#line 2406 "configure"' > conftest.$ac_ext
-  if { (eval echo configure:2407: \"$ac_compile\") 1>&5; (eval $ac_compile) 2>&5; }; then
+  echo '#line 2421 "configure"' > conftest.$ac_ext
+  if { (eval echo configure:2422: \"$ac_compile\") 1>&5; (eval $ac_compile) 2>&5; }; then
     case "`/usr/bin/file conftest.o`" in
     *32-bit*)
       LD="${LD-ld} -32"
@@ -2424,19 +2439,19 @@ case "$host" in
   SAVE_CFLAGS="$CFLAGS"
   CFLAGS="$CFLAGS -belf"
   echo $ac_n "checking whether the C compiler needs -belf""... $ac_c" 1>&6
-echo "configure:2428: checking whether the C compiler needs -belf" >&5
+echo "configure:2443: checking whether the C compiler needs -belf" >&5
 if eval "test \"`echo '$''{'lt_cv_cc_needs_belf'+set}'`\" = set"; then
   echo $ac_n "(cached) $ac_c" 1>&6
 else
   cat > conftest.$ac_ext <<EOF
-#line 2433 "configure"
+#line 2448 "configure"
 #include "confdefs.h"
 
 int main() {
 
 ; return 0; }
 EOF
-if { (eval echo configure:2440: \"$ac_link\") 1>&5; (eval $ac_link) 2>&5; } && test -s conftest${ac_exeext}; then
+if { (eval echo configure:2455: \"$ac_link\") 1>&5; (eval $ac_link) 2>&5; } && test -s conftest${ac_exeext}; then
   rm -rf conftest*
   lt_cv_cc_needs_belf=yes
 else
@@ -2551,9 +2566,9 @@ esac
 
 
 echo $ac_n "checking for IPv6 structures""... $ac_c" 1>&6
-echo "configure:2555: checking for IPv6 structures" >&5
+echo "configure:2570: checking for IPv6 structures" >&5
 cat > conftest.$ac_ext <<EOF
-#line 2557 "configure"
+#line 2572 "configure"
 #include "confdefs.h"
 
 #include <sys/types.h>
@@ -2563,7 +2578,7 @@ int main() {
 struct sockaddr_in6 sin6; return (0);
 ; return 0; }
 EOF
-if { (eval echo configure:2567: \"$ac_compile\") 1>&5; (eval $ac_compile) 2>&5; }; then
+if { (eval echo configure:2582: \"$ac_compile\") 1>&5; (eval $ac_compile) 2>&5; }; then
   rm -rf conftest*
   echo "$ac_t""yes" 1>&6
 	ISC_NET_HAVEIPV6="#define ISC_NET_HAVEIPV6 1"
@@ -2586,12 +2601,12 @@ rm -f conftest*
 
 
 echo $ac_n "checking for inet_ntop""... $ac_c" 1>&6
-echo "configure:2590: checking for inet_ntop" >&5
+echo "configure:2605: checking for inet_ntop" >&5
 if eval "test \"`echo '$''{'ac_cv_func_inet_ntop'+set}'`\" = set"; then
   echo $ac_n "(cached) $ac_c" 1>&6
 else
   cat > conftest.$ac_ext <<EOF
-#line 2595 "configure"
+#line 2610 "configure"
 #include "confdefs.h"
 /* System header to define __stub macros and hopefully few prototypes,
     which can conflict with char inet_ntop(); below.  */
@@ -2614,7 +2629,7 @@ inet_ntop();
 
 ; return 0; }
 EOF
-if { (eval echo configure:2618: \"$ac_link\") 1>&5; (eval $ac_link) 2>&5; } && test -s conftest${ac_exeext}; then
+if { (eval echo configure:2633: \"$ac_link\") 1>&5; (eval $ac_link) 2>&5; } && test -s conftest${ac_exeext}; then
   rm -rf conftest*
   eval "ac_cv_func_inet_ntop=yes"
 else
@@ -2638,12 +2653,12 @@ ISC_EXTRA_OBJS="$ISC_EXTRA_OBJS inet_ntop.$O"
 fi
 
 echo $ac_n "checking for inet_pton""... $ac_c" 1>&6
-echo "configure:2642: checking for inet_pton" >&5
+echo "configure:2657: checking for inet_pton" >&5
 if eval "test \"`echo '$''{'ac_cv_func_inet_pton'+set}'`\" = set"; then
   echo $ac_n "(cached) $ac_c" 1>&6
 else
   cat > conftest.$ac_ext <<EOF
-#line 2647 "configure"
+#line 2662 "configure"
 #include "confdefs.h"
 /* System header to define __stub macros and hopefully few prototypes,
     which can conflict with char inet_pton(); below.  */
@@ -2666,7 +2681,7 @@ inet_pton();
 
 ; return 0; }
 EOF
-if { (eval echo configure:2670: \"$ac_link\") 1>&5; (eval $ac_link) 2>&5; } && test -s conftest${ac_exeext}; then
+if { (eval echo configure:2685: \"$ac_link\") 1>&5; (eval $ac_link) 2>&5; } && test -s conftest${ac_exeext}; then
   rm -rf conftest*
   eval "ac_cv_func_inet_pton=yes"
 else
@@ -2690,12 +2705,12 @@ ISC_EXTRA_OBJS="$ISC_EXTRA_OBJS inet_pton.$O"
 fi
 
 echo $ac_n "checking for inet_aton""... $ac_c" 1>&6
-echo "configure:2694: checking for inet_aton" >&5
+echo "configure:2709: checking for inet_aton" >&5
 if eval "test \"`echo '$''{'ac_cv_func_inet_aton'+set}'`\" = set"; then
   echo $ac_n "(cached) $ac_c" 1>&6
 else
   cat > conftest.$ac_ext <<EOF
-#line 2699 "configure"
+#line 2714 "configure"
 #include "confdefs.h"
 /* System header to define __stub macros and hopefully few prototypes,
     which can conflict with char inet_aton(); below.  */
@@ -2718,7 +2733,7 @@ inet_aton();
 
 ; return 0; }
 EOF
-if { (eval echo configure:2722: \"$ac_link\") 1>&5; (eval $ac_link) 2>&5; } && test -s conftest${ac_exeext}; then
+if { (eval echo configure:2737: \"$ac_link\") 1>&5; (eval $ac_link) 2>&5; } && test -s conftest${ac_exeext}; then
   rm -rf conftest*
   eval "ac_cv_func_inet_aton=yes"
 else
@@ -2956,6 +2971,7 @@ s%@MKDEPCC@%$MKDEPCC%g
 s%@MKDEPCFLAGS@%$MKDEPCFLAGS%g
 s%@MKDEPPROG@%$MKDEPPROG%g
 s%@ISC_NET_HAVESALEN@%$ISC_NET_HAVESALEN%g
+s%@ISC_NET_MSGHDRFLAVOR@%$ISC_NET_MSGHDRFLAVOR%g
 s%@build@%$build%g
 s%@build_alias@%$build_alias%g
 s%@build_cpu@%$build_cpu%g
diff --git a/configure.in b/configure.in
index cf9a783e88..ae2fd9e1ff 100644
--- a/configure.in
+++ b/configure.in
@@ -13,7 +13,7 @@ dnl PROFITS, WHETHER IN AN ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS
 dnl ACTION, ARISING OUT OF OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS
 dnl SOFTWARE.
 
-AC_REVISION($Revision: 1.51 $)
+AC_REVISION($Revision: 1.52 $)
 
 AC_PREREQ(2.13)
 
@@ -241,14 +241,6 @@ case "$host" in
 		dnl Turn on 4.4BSD style sa_len support.
 		AC_DEFINE(_SOCKADDR_LEN)
 		;;
-	*-sun-solaris*)
-		dnl Solaris has yet another trick to get 4.4BSD behavior
-		AC_DEFINE(NEED_XPG4_2_BEFORE_SOCKET_H)
-		;;
-	*-hp-hpux*)
-		dnl And HP has to be different, too.
-		AC_DEFINE(NEED_XSE_BEFORE_SOCKET_H)
-		;;
 esac
 
 dnl
@@ -266,6 +258,21 @@ AC_TRY_COMPILE([
 	ISC_NET_HAVESALEN="#undef ISC_NET_HAVESALEN"])
 AC_SUBST(ISC_NET_HAVESALEN)
 
+dnl
+dnl Look for a 4.4BSD or 4.3BSD struct msghdr
+dnl
+
+AC_MSG_CHECKING(for struct msghdr flavor)
+AC_TRY_COMPILE([
+#include <sys/types.h>
+#include <sys/socket.h>],
+[struct msghdr msg; msg.msg_flags = 0; return (0);],
+	[AC_MSG_RESULT(4.4BSD)
+	ISC_NET_MSGHDRFLAVOR="#define ISC_NET_BSD44MSGHDR 1"],
+	[AC_MSG_RESULT(4.3BSD)
+	ISC_NET_MSGHDRFLAVOR="#define ISC_NET_BSD43MSGHDR 1"])
+AC_SUBST(ISC_NET_MSGHDRFLAVOR)
+
 dnl
 dnl Look for a sysctl call to get the list of network interfaces.
 dnl
diff --git a/lib/isc/unix/include/isc/net.h.in b/lib/isc/unix/include/isc/net.h.in
index b17c43e450..fad5a41ded 100644
--- a/lib/isc/unix/include/isc/net.h.in
+++ b/lib/isc/unix/include/isc/net.h.in
@@ -115,6 +115,11 @@
 #include <isc/ipv6.h>
 #endif
 
+/*
+ * Define either ISC_NET_BSD44MSGHDR or ISC_NET_BSD43MSGHDR
+ */
+@ISC_NET_MSGHDRFLAVOR@
+
 /***
  *** Functions.
  ***/
diff --git a/lib/isc/unix/socket.c b/lib/isc/unix/socket.c
index 2442853e19..6cccabb967 100644
--- a/lib/isc/unix/socket.c
+++ b/lib/isc/unix/socket.c
@@ -19,17 +19,6 @@
 
 #include <sys/types.h>
 #include <sys/uio.h>
-#if defined(NEED_XPG4_2_BEFORE_SOCKET_H) && !defined(_XPG4_2)
-#define _XPG4_2
-#include <sys/socket.h>
-#undef _XPG4_2
-#elif defined(NEED_XSE_BEFORE_SOCKET_H) && !defined(_XOPEN_SOURCE_EXTENDED)
-#define _XOPEN_SOURCE_EXTENDED
-#include <sys/socket.h>
-#undef _XOPEN_SOURCE_EXTENDED
-#else
-#include <sys/socket.h>
-#endif
 
 #include <errno.h>
 #include <stddef.h>
@@ -42,6 +31,7 @@
 #include <isc/error.h>
 #include <isc/thread.h>
 #include <isc/mutex.h>
+#include <isc/net.h>
 #include <isc/condition.h>
 #include <isc/socket.h>
 #include <isc/list.h>
@@ -277,8 +267,10 @@ make_nonblock(int fd)
 static void
 process_cmsg(isc_socket_t *sock, struct msghdr *msg, isc_socketevent_t *dev)
 {
-	struct cmsghdr *cm;
 
+	(void)sock;
+
+#ifdef ISC_NET_BSD44MSGHDR
 #ifdef MSG_TRUNC
 	if ((msg->msg_flags & MSG_TRUNC) == MSG_TRUNC)
 		dev->attributes |= ISC_SOCKEVENTATTR_TRUNC;
@@ -291,11 +283,8 @@ process_cmsg(isc_socket_t *sock, struct msghdr *msg, isc_socketevent_t *dev)
 
 	if (msg->msg_controllen == 0 || msg->msg_control == NULL)
 		return;
+#endif /* ISC_NET_BSD44MSGHDR */
 
-	/*
-	 * Pull off the options
-	 */
-	
 }
 
 /*
@@ -455,7 +444,6 @@ isc_socket_create(isc_socketmgr_t *manager, int pf, isc_sockettype_t type,
 {
 	isc_socket_t *sock = NULL;
 	isc_result_t ret;
-	int on = 1;
 
 	REQUIRE(VALID_MANAGER(manager));
 	REQUIRE(socketp != NULL && *socketp == NULL);
@@ -499,6 +487,7 @@ isc_socket_create(isc_socketmgr_t *manager, int pf, isc_sockettype_t type,
 		return (ISC_R_UNEXPECTED);
 	}
 
+#if 0
 #ifdef SO_TIMESTAMP
 	if (type == isc_sockettype_udp
 	    && setsockopt(sock->fd, SOL_SOCKET, SO_TIMESTAMP,
@@ -507,6 +496,7 @@ isc_socket_create(isc_socketmgr_t *manager, int pf, isc_sockettype_t type,
 				 sock->fd);
 		/* Press on... */
 	}
+#endif
 #endif
 
 	sock->references = 1;
@@ -945,14 +935,15 @@ internal_recv(isc_task_t *me, isc_event_t *ev)
 		}
 		msghdr.msg_iov = &iov;
 		msghdr.msg_iovlen = 1;
-#ifdef notyet
-		msghdr.msg_control = (void *)sock->cmsg;
-		msghdr.msg_controllen = sizeof (sock->cmsg);
-#else
+
+#ifdef ISC_NET_BSD44MSGHDR
 		msghdr.msg_control = NULL;
 		msghdr.msg_controllen = 0;
-#endif
 		msghdr.msg_flags = 0;
+#else
+		msghdr.msg_accrights = NULL;
+		msghdr.msg_accrightslen = 0;
+#endif
 
 		cc = recvmsg(sock->fd, &msghdr, 0);
 
@@ -1141,9 +1132,15 @@ internal_send(isc_task_t *me, isc_event_t *ev)
 
 		msghdr.msg_iov = &iov;
 		msghdr.msg_iovlen = 1;
+
+#ifdef ISC_NET_BSD44MSGHDR
 		msghdr.msg_control = NULL;
 		msghdr.msg_controllen = 0;
 		msghdr.msg_flags = 0;
+#else
+		msghdr.msg_accrights = NULL;
+		msghdr.msg_accrightslen = 0;
+#endif
 
 		cc = sendmsg(sock->fd, &msghdr, 0);
 
@@ -1693,14 +1690,15 @@ isc_socket_recv(isc_socket_t *sock, isc_region_t *region, unsigned int minimum,
 	}
 	msghdr.msg_iov = &iov;
 	msghdr.msg_iovlen = 1;
-#ifdef notyet
-	msghdr.msg_control = (void *)sock->cmsg;
-	msghdr.msg_controllen = sizeof (sock->cmsg);
-#else
+
+#ifdef ISC_NET_BSD44MSGHDR
 	msghdr.msg_control = NULL;
 	msghdr.msg_controllen = 0;
-#endif
 	msghdr.msg_flags = 0;
+#else
+	msghdr.msg_accrights = NULL;
+	msghdr.msg_accrightslen = 0;
+#endif
 
 	cc = recvmsg(sock->fd, &msghdr, 0);
 	if (sock->type == isc_sockettype_udp)
@@ -1892,9 +1890,15 @@ isc_socket_sendto(isc_socket_t *sock, isc_region_t *region,
 
 	msghdr.msg_iov = &iov;
 	msghdr.msg_iovlen = 1;
+
+#ifdef ISC_NET_BSD44MSGHDR
 	msghdr.msg_control = NULL;
 	msghdr.msg_controllen = 0;
 	msghdr.msg_flags = 0;
+#else
+	msghdr.msg_accrights = NULL;
+	msghdr.msg_accrightslen = 0;
+#endif
 
 	cc = sendmsg(sock->fd, &msghdr, 0);
 
@@ -2247,7 +2251,7 @@ internal_connect(isc_task_t *me, isc_event_t *ev)
 	ISC_SOCKADDR_LEN_T optlen;
 
 	(void)me;
-	INSIST(ev->type = ISC_SOCKEVENT_INTW);
+	INSIST(ev->type == ISC_SOCKEVENT_INTW);
 
 	sock = ev->sender;
 	INSIST(VALID_SOCKET(sock));
@@ -2285,7 +2289,7 @@ internal_connect(isc_task_t *me, isc_event_t *ev)
 	 */
 	optlen = sizeof(cc);
 	if (getsockopt(sock->fd, SOL_SOCKET, SO_ERROR,
-		       (char *)&cc, &optlen) < 0)
+		       (void *)&cc, (void *)&optlen) < 0)
 		cc = errno;
 	else
 		errno = cc;
@@ -2361,7 +2365,7 @@ isc_socket_getsockname(isc_socket_t *sock, isc_sockaddr_t *addressp)
 	LOCK(&sock->lock);
 
 	len = sizeof addressp->type;
-	if (getsockname(sock->fd, &addressp->type.sa, &len) < 0) {
+	if (getsockname(sock->fd, &addressp->type.sa, (void *)&len) < 0) {
 		UNEXPECTED_ERROR(__FILE__, __LINE__,
 				 "getsockname: %s", strerror(errno));
 		UNLOCK(&sock->lock);