diff --git a/configure.ac b/configure.ac
index cfc2122b08..efdef27c9a 100644
--- a/configure.ac
+++ b/configure.ac
@@ -319,21 +319,30 @@ AC_SUBST(PPPD_PLUGIN_DIR)
 AC_ARG_WITH([dhclient], AS_HELP_STRING([--with-dhclient=yes|no|path], [Enable dhclient 4.x support]))
 # If a full path is given, use that and do not test if it works or not.
 case "${with_dhclient}" in
+	# NM only works with ISC dhclient - other derivatives don't have
+	# the same userland.  dhclient 4.x is required for IPv6 support;
+	# with older versions NM won't be able to use DHCPv6.
+
 	/*)
 		DHCLIENT_PATH="${with_dhclient}"
+		DHCLIENT_VERSION=4
+		if test -x "${with_dhclient}"; then
+			case `"${with_dhclient}" --version 2>&1` in
+				"isc-dhclient-4"*) DHCLIENT_VERSION=4; break;;
+				"isc-dhclient-V3"*) DHCLIENT_VERSION=3; break;;
+			esac
+		fi
 		AC_MSG_NOTICE(using dhclient at ${DHCLIENT_PATH})
 		;;
 	no)	AC_MSG_NOTICE(dhclient support disabled)
 		;;
 	*)
 		AC_MSG_CHECKING(for dhclient)
-		# NM only works with ISC dhclient - other derivatives don't have
-		# the same userland.  NM also requires dhclient 4.x since older
-		# versions do not have IPv6 support.
 		for path in /sbin /usr/sbin /usr/pkg/sbin /usr/local/sbin; do
 			test -x "${path}/dhclient" || continue
 			case `"$path/dhclient" --version 2>&1` in
-				"isc-dhclient-4"*) DHCLIENT_PATH="$path/dhclient"; break;;
+				"isc-dhclient-4"*) DHCLIENT_PATH="$path/dhclient"; DHCLIENT_VERSION=4; break;;
+				"isc-dhclient-V3"*) DHCLIENT_PATH="$path/dhclient"; DHCLIENT_VERSION=3; break;;
 			esac
 		done
 		if test -n "${DHCLIENT_PATH}"; then
@@ -554,6 +563,7 @@ echo
 
 if test -n "${DHCLIENT_PATH}"; then
 	echo ISC dhclient support: ${DHCLIENT_PATH}
+	echo ISC dhclient version: ${DHCLIENT_VERSION}
 else
 	echo ISC dhclient support: no
 fi
diff --git a/src/dhcp-manager/Makefile.am b/src/dhcp-manager/Makefile.am
index f75e6b3d07..4c5408701e 100644
--- a/src/dhcp-manager/Makefile.am
+++ b/src/dhcp-manager/Makefile.am
@@ -29,6 +29,7 @@ libdhcp_manager_la_CPPFLAGS = \
 	-DLIBEXECDIR=\"$(libexecdir)\" \
 	-DLOCALSTATEDIR=\"$(localstatedir)\" \
 	-DDHCLIENT_PATH=\"$(DHCLIENT_PATH)\" \
+	-DDHCLIENT_V$(DHCLIENT_VERSION) \
 	-DDHCPCD_PATH=\"$(DHCPCD_PATH)\"
 
 libdhcp_manager_la_LIBADD = \
diff --git a/src/dhcp-manager/nm-dhcp-dhclient.c b/src/dhcp-manager/nm-dhcp-dhclient.c
index cae7df22c3..13caa028f9 100644
--- a/src/dhcp-manager/nm-dhcp-dhclient.c
+++ b/src/dhcp-manager/nm-dhcp-dhclient.c
@@ -45,7 +45,11 @@ G_DEFINE_TYPE (NMDHCPDhclient, nm_dhcp_dhclient, NM_TYPE_DHCP_CLIENT)
 #define NM_DHCP_DHCLIENT_GET_PRIVATE(o) (G_TYPE_INSTANCE_GET_PRIVATE ((o), NM_TYPE_DHCP_DHCLIENT, NMDHCPDhclientPrivate))
 
 #if defined(TARGET_DEBIAN) || defined(TARGET_SUSE) || defined(TARGET_MANDRIVA)
+#if defined(DHCLIENT_V3)
+#define NM_DHCLIENT_LEASE_DIR			LOCALSTATEDIR "/lib/dhcp3"
+#else
 #define NM_DHCLIENT_LEASE_DIR           LOCALSTATEDIR "/lib/dhcp"
+#endif
 #else
 #define NM_DHCLIENT_LEASE_DIR           LOCALSTATEDIR "/lib/dhclient"
 #endif
@@ -437,7 +441,11 @@ create_dhclient_config (const char *iface,
 #if defined(TARGET_SUSE)
 	orig = g_strdup (SYSCONFDIR "/dhclient.conf");
 #elif defined(TARGET_DEBIAN) || defined(TARGET_GENTOO)
+#if defined(DHCLIENT_V3)
+	orig = g_strdup (SYSCONFDIR "/dhcp3/dhclient.conf");
+#else
 	orig = g_strdup (SYSCONFDIR "/dhcp/dhclient.conf");
+#endif
 #else
 	orig = g_strdup_printf (SYSCONFDIR "/dhclient-%s.conf", iface);
 #endif
@@ -499,12 +507,20 @@ dhclient_start (NMDHCPClient *client,
 	guint log_domain;
 
 	g_return_val_if_fail (priv->pid_file == NULL, -1);
-	g_return_val_if_fail (ip_opt != NULL, -1);
 
 	iface = nm_dhcp_client_get_iface (client);
 	uuid = nm_dhcp_client_get_uuid (client);
 	ipv6 = nm_dhcp_client_get_ipv6 (client);
 
+#if defined(DHCLIENT_V3)
+	if (ipv6) {
+		nm_log_warn (log_domain, "(%s): ISC dhcp3 does not support IPv6", iface);
+		return -1;
+	}
+#else
+	g_return_val_if_fail (ip_opt != NULL, -1);
+#endif
+
 	log_domain = ipv6 ? LOGD_DHCP6 : LOGD_DHCP4;
 
 	priv->pid_file = g_strdup_printf (LOCALSTATEDIR "/run/dhclient%s-%s.pid",
@@ -536,10 +552,11 @@ dhclient_start (NMDHCPClient *client,
 
 	g_ptr_array_add (argv, (gpointer) "-d");
 
+#if !defined(DHCLIENT_V3)
 	g_ptr_array_add (argv, (gpointer) ip_opt);
-
 	if (mode_opt)
 		g_ptr_array_add (argv, (gpointer) mode_opt);
+#endif
 
 	g_ptr_array_add (argv, (gpointer) "-sf");	/* Set script file */
 	g_ptr_array_add (argv, (gpointer) ACTION_SCRIPT_PATH );