diff --git a/tests/compat.sh b/tests/compat.sh
index 28c8021..cff581d 100755
--- a/tests/compat.sh
+++ b/tests/compat.sh
@@ -806,6 +806,23 @@
     exit 1
 }
 
+# wait for client to terminate and set EXIT
+# must be called right after starting the client
+wait_client_done() {
+    CLI_PID=$!
+
+    ( sleep "$DOG_DELAY"; echo "TIMEOUT" >> $CLI_OUT; kill $CLI_PID ) &
+    WATCHDOG_PID=$!
+
+    wait $CLI_PID
+    EXIT=$?
+
+    kill $WATCHDOG_PID
+    wait $WATCHDOG_PID
+
+    echo "EXIT: $EXIT" >> $CLI_OUT
+}
+
 # run_client <name> <cipher>
 run_client() {
     # announce what we're going to do
@@ -823,8 +840,8 @@
             CLIENT_CMD="$OPENSSL_CMD s_client $O_CLIENT_ARGS -cipher $2"
             log "$CLIENT_CMD"
             echo "$CLIENT_CMD" > $CLI_OUT
-            ( echo -e 'GET HTTP/1.0'; echo; ) | $CLIENT_CMD >> $CLI_OUT 2>&1
-            EXIT=$?
+            ( echo -e 'GET HTTP/1.0'; echo; ) | $CLIENT_CMD >> $CLI_OUT 2>&1 &
+            wait_client_done
 
             if [ "$EXIT" == "0" ]; then
                 RESULT=0
@@ -841,8 +858,8 @@
             CLIENT_CMD="$GNUTLS_CLI $G_CLIENT_ARGS --priority $G_PRIO_MODE:$2 localhost"
             log "$CLIENT_CMD"
             echo "$CLIENT_CMD" > $CLI_OUT
-            ( echo -e 'GET HTTP/1.0'; echo; ) | $CLIENT_CMD >> $CLI_OUT 2>&1
-            EXIT=$?
+            ( echo -e 'GET HTTP/1.0'; echo; ) | $CLIENT_CMD >> $CLI_OUT 2>&1 &
+            wait_client_done
 
             if [ "$EXIT" == "0" ]; then
                 RESULT=0
@@ -866,8 +883,8 @@
             fi
             log "$CLIENT_CMD"
             echo "$CLIENT_CMD" > $CLI_OUT
-            $CLIENT_CMD >> $CLI_OUT 2>&1
-            EXIT=$?
+            $CLIENT_CMD >> $CLI_OUT 2>&1 &
+            wait_client_done
 
             case $EXIT in
                 "0")    RESULT=0    ;;
@@ -962,6 +979,13 @@
 SRV_OUT="srv_out.$$"
 CLI_OUT="cli_out.$$"
 
+# client timeout delay: be more patient with valgrind
+if [ "$MEMCHECK" -gt 0 ]; then
+    DOG_DELAY=30
+else
+    DOG_DELAY=10
+fi
+
 trap cleanup INT TERM HUP
 
 for VERIFY in $VERIFIES; do
diff --git a/tests/ssl-opt.sh b/tests/ssl-opt.sh
index 79de1b7..225df96 100755
--- a/tests/ssl-opt.sh
+++ b/tests/ssl-opt.sh
@@ -150,6 +150,23 @@
     fi
 }
 
+# wait for client to terminate and set CLI_EXIT
+# must be called right after starting the client
+wait_client_done() {
+    CLI_PID=$!
+
+    ( sleep "$DOG_DELAY"; echo "TIMEOUT" >> $CLI_OUT; kill $CLI_PID ) &
+    WATCHDOG_PID=$!
+
+    wait $CLI_PID
+    CLI_EXIT=$?
+
+    kill $WATCHDOG_PID
+    wait $WATCHDOG_PID
+
+    echo "EXIT: $CLI_EXIT" >> $CLI_OUT
+}
+
 # Usage: run_test name srv_cmd cli_cmd cli_exit [option [...]]
 # Options:  -s pattern  pattern that must be present in server output
 #           -c pattern  pattern that must be present in client output
@@ -192,10 +209,10 @@
     $SRV_CMD >> $SRV_OUT 2>&1 &
     SRV_PID=$!
     wait_server_start
+
     echo "$CLI_CMD" > $CLI_OUT
-    eval "$CLI_CMD" >> $CLI_OUT 2>&1
-    CLI_EXIT=$?
-    echo "EXIT: $CLI_EXIT" >> $CLI_OUT
+    eval "$CLI_CMD" >> $CLI_OUT 2>&1 &
+    wait_client_done
 
     # kill the server
     kill $SRV_PID