diff --git a/ChangeLog b/ChangeLog
index 069966041..daa6e503c 100644
--- a/ChangeLog
+++ b/ChangeLog
@@ -27,6 +27,7 @@ Bugfix
      mbedtls_ssl_conf_curves. #373
    * Fix issue in ssl_fork_server which was preventing it from functioning. #429
    * Fix memory leaks in test framework
+   * Fix test in ssl-opt.sh that does not run properly with valgrind
 
 Changes
    * On ARM platforms, when compiling with -O0 with GCC, Clang or armcc5,
diff --git a/tests/ssl-opt.sh b/tests/ssl-opt.sh
index c08af7b04..536add274 100755
--- a/tests/ssl-opt.sh
+++ b/tests/ssl-opt.sh
@@ -130,6 +130,13 @@ not_with_valgrind() {
     fi
 }
 
+# skip the next test if valgrind is NOT in use
+only_with_valgrind() {
+    if [ "$MEMCHECK" -eq 0 ]; then
+        SKIP_NEXT="YES"
+    fi
+}
+
 # multiply the client timeout delay by the given factor for the next test
 needs_more_time() {
     CLI_DELAY_FACTOR=$1
@@ -408,32 +415,33 @@ run_test() {
 
     # check other assertions
     # lines beginning with == are added by valgrind, ignore them
+    # lines with 'Serious error when reading debug info', are valgrind issues as well
     while [ $# -gt 0 ]
     do
         case $1 in
             "-s")
-                if grep -v '^==' $SRV_OUT | grep "$2" >/dev/null; then :; else
+                if grep -v '^==' $SRV_OUT | grep -v 'Serious error when reading debug info' | grep "$2" >/dev/null; then :; else
                     fail "-s $2"
                     return
                 fi
                 ;;
 
             "-c")
-                if grep -v '^==' $CLI_OUT | grep "$2" >/dev/null; then :; else
+                if grep -v '^==' $CLI_OUT | grep -v 'Serious error when reading debug info' | grep "$2" >/dev/null; then :; else
                     fail "-c $2"
                     return
                 fi
                 ;;
 
             "-S")
-                if grep -v '^==' $SRV_OUT | grep "$2" >/dev/null; then
+                if grep -v '^==' $SRV_OUT | grep -v 'Serious error when reading debug info' | grep "$2" >/dev/null; then
                     fail "-S $2"
                     return
                 fi
                 ;;
 
             "-C")
-                if grep -v '^==' $CLI_OUT | grep "$2" >/dev/null; then
+                if grep -v '^==' $CLI_OUT | grep -v 'Serious error when reading debug info' | grep "$2" >/dev/null; then
                     fail "-C $2"
                     return
                 fi
@@ -3048,13 +3056,22 @@ run_test    "DTLS client reconnect from same port: reconnect" \
             -S "The operation timed out" \
             -s "Client initiated reconnection from same port"
 
-run_test    "DTLS client reconnect from same port: reconnect, nbio" \
+not_with_valgrind # server/client too slow to respond in time (next test has higher timeouts)
+run_test    "DTLS client reconnect from same port: reconnect, nbio, no valgrind" \
             "$P_SRV dtls=1 exchanges=2 read_timeout=1000 nbio=2" \
             "$P_CLI dtls=1 exchanges=2 debug_level=2 hs_timeout=500-1000 reconnect_hard=1" \
             0 \
             -S "The operation timed out" \
             -s "Client initiated reconnection from same port"
 
+only_with_valgrind # Only with valgrind, do previous test but with higher read_timeout and hs_timeout
+run_test    "DTLS client reconnect from same port: reconnect, nbio, valgrind" \
+            "$P_SRV dtls=1 exchanges=2 read_timeout=2000 nbio=2 hs_timeout=1500-6000" \
+            "$P_CLI dtls=1 exchanges=2 debug_level=2 hs_timeout=1500-3000 reconnect_hard=1" \
+            0 \
+            -S "The operation timed out" \
+            -s "Client initiated reconnection from same port"
+
 run_test    "DTLS client reconnect from same port: no cookies" \
             "$P_SRV dtls=1 exchanges=2 read_timeout=1000 cookies=0" \
             "$P_CLI dtls=1 exchanges=2 debug_level=2 hs_timeout=500-8000 reconnect_hard=1" \