diff --git a/scripts/dtls.test b/scripts/dtls.test
index 2d6f58714..52f768ecd 100755
--- a/scripts/dtls.test
+++ b/scripts/dtls.test
@@ -30,6 +30,10 @@ SERVER_PORT=4321
 KEY_UPDATE_SIZE=35
 NUM_TESTS_FAILED=0
 
+if [ "$DTLS_VERSION" = "-v4" ]; then
+    UDP_PROXY_EXTRA_ARGS="-u"
+fi
+
 # $WOLFSSL_ROOT/tests/unit.test tests/test-dtls13.conf
 
 set -o pipefail
@@ -40,7 +44,7 @@ prepend() { # Usage: cmd 2>&1 | prepend "sometext "
 run_test() { # usage: run_test "<udp-proxy args>" "<server args>" "<client args>"
     stdbuf -oL -eL $WOLFSSL_ROOT/examples/server/server -u -p$SERVER_PORT $DTLS_VERSION $2 2>&1 | prepend "[server] " &
     SERVER_PID=$!
-    stdbuf -oL -eL $UDP_PROXY_BIN -p $PROXY_PORT -s 127.0.0.1:$SERVER_PORT -u $1 2>&1 | prepend "[udp-proxy] " &
+    stdbuf -oL -eL $UDP_PROXY_BIN -p $PROXY_PORT -s 127.0.0.1:$SERVER_PORT $UDP_PROXY_EXTRA_ARGS $1 2>&1 | prepend "[udp-proxy] " &
     UDP_PROXY_PID=$(($! - 1))
     echo "UDP-proxy: $UDP_PROXY_PID"
     sleep 0.2