diff --git a/t_server/original/client_vm/bin/t_client.sh b/t_server/original/client_vm/bin/t_client.sh
index 98b53cc..37fdaff 100755
--- a/t_server/original/client_vm/bin/t_client.sh
+++ b/t_server/original/client_vm/bin/t_client.sh
@@ -262,6 +262,20 @@ get_ifconfig_route()
     esac
 }
 
+# ----------------------------------------------------------
+# check ifconfig output on whether some address is in "tentative" state
+# repeats calling get_ifconfig_route until it does not
+#  arg1: log file
+check_tentative_state()
+{
+    logfile="$1"
+    while grep -q tentative $logfile; do
+        output "waiting for tentative state to end"
+        sleep 1
+        get_ifconfig_route >$logfile
+    done
+}
+
 # ----------------------------------------------------------
 # check ifconfig
 #  arg1: "4" or "6" -> for message
@@ -389,6 +403,7 @@ do
 
     output "save pre-openvpn ifconfig + route"
     get_ifconfig_route >$LOGDIR/$SUF:ifconfig_route_pre.txt
+    check_tentative_state $LOGDIR/$SUF:ifconfig_route_pre.txt
 
     output "\nrun pre-openvpn ping tests - targets must not be reachable..."
     run_ping_tests 4 want_fail "$ping4_hosts"
@@ -489,6 +504,7 @@ do
     # compare whether anything changed in ifconfig/route setup?
     output "save ifconfig+route"
     get_ifconfig_route >$LOGDIR/$SUF:ifconfig_route.txt
+    check_tentative_state $LOGDIR/$SUF:ifconfig_route.txt
 
     if [ "$expect_ifconfig4" = "-" ] ; then
         output "skip ifconfig+route check"
@@ -527,6 +543,7 @@ do
 
     output "\nsave post-openvpn ifconfig + route..."
     get_ifconfig_route >$LOGDIR/$SUF:ifconfig_route_post.txt
+    check_tentative_state $LOGDIR/$SUF:ifconfig_route_post.txt
 
     output -n "compare pre- and post-openvpn ifconfig + route..."
     if diff $LOGDIR/$SUF:ifconfig_route_pre.txt \
diff --git a/t_server/original/client_vm/t_client.master/t_client.rc b/t_server/original/client_vm/t_client.master/t_client.rc
index fb502b4..cdc1801 100644
--- a/t_server/original/client_vm/t_client.master/t_client.rc
+++ b/t_server/original/client_vm/t_client.master/t_client.rc
@@ -28,7 +28,7 @@ FPING_EXTRA_ARGS="-C 5 -p 50"
 # For proxy tests
 FPING_PROXY_ARGS="-C 5 -p 100"
 # For slow tests (4/9)
-FPING_SLOW_ARGS="-C 10 -p 200"
+FPING_SLOW_ARGS="-C 20 -p 200"
 
 #
 # remote host (used as macro below)
@@ -315,10 +315,13 @@ OPENVPN_CONF_3m="$OPENVPN_CONF_3 --max-packet-size 145"
 EXPECT_IFCONFIG4_3m=$EXPECT_IFCONFIG4_3
 PING4_HOSTS_3m="$PING4_HOSTS_3"
 
+LLDADDR_4="--lladdr 02:04:02:07:00:$openvpn_version"
+
 # Test 4: UDP / p2mp tap
 #
 RUN_TITLE_4="udp4 / p2pm / tap"
-OPENVPN_CONF_4="$OPENVPN_BASE_P2MP --dev tap --proto ${UDP4} --remote $REMOTE --port 51196 --route-ipv6 fd00:abcd:195::/48 fd00:abcd:204:4::ffff"
+BASE_CONF_4="$OPENVPN_BASE_P2MP --dev tap --remote $REMOTE --port 51196 $LLDADDR_4"
+OPENVPN_CONF_4="$BASE_CONF_4 --proto ${UDP4} --route-ipv6 fd00:abcd:195::/48 fd00:abcd:204:4::ffff"
 if ! needs_openvpn 24; then
   OPENVPN_CONF_4="$OPENVPN_CONF_4 --tun-ipv6"
 fi
@@ -331,7 +334,7 @@ PING6_HOSTS_4="fd00:abcd:204:4::1 fd00:abcd:204:0::1 fd00:abcd:204:4::a:200 fd00
 #
 RUN_TITLE_4a="udp6 / p2pm / tap3 / topo subnet"
 CHECK_SKIP_4a="needs_openvpn 24" # subnet
-OPENVPN_CONF_4a="$OPENVPN_BASE_P2MP --dev tap3 --proto udp6 --remote $REMOTE --port 51196 --topology subnet"
+OPENVPN_CONF_4a="$BASE_CONF_4 --proto udp6 --topology subnet"
 EXPECT_IFCONFIG4_4a=$EXPECT_IFCONFIG4_4
 EXPECT_IFCONFIG6_4a=$EXPECT_IFCONFIG6_4
 FPING_ARGS_4a="$FPING_SLOW_ARGS"
@@ -342,7 +345,7 @@ PING6_HOSTS_4a="$PING6_HOSTS_4"
 #
 RUN_TITLE_4b="udp / p2pm / tap / ipv6-only (pull-filter)"
 CHECK_SKIP_4b="needs_openvpn 25" # ipv6-only doesn't work
-OPENVPN_CONF_4b="$OPENVPN_BASE_P2MP --dev tap --proto udp --remote $REMOTE --port 51196 --pull-filter accept ifconfig- --pull-filter ignore ifconfig"
+OPENVPN_CONF_4b="$BASE_CONF_4 --proto udp --pull-filter accept ifconfig- --pull-filter ignore ifconfig"
 EXPECT_IFCONFIG4_4b=-
 EXPECT_IFCONFIG6_4b=$EXPECT_IFCONFIG6_4
 FPING_ARGS_4b="$FPING_SLOW_ARGS"