diff --git a/configure b/configure
index cc13590fdb..ee96d14f78 100755
--- a/configure
+++ b/configure
@@ -23635,7 +23635,7 @@ if test "x$HPCXX" = "xyes"; then
 fi
 
 if test "x$COMPAQCXX" = "xyes"; then
-                                CXXFLAGS="-w0 -msg_disable basclsnondto,unrimpret,intconlosbit"
+                                CXXFLAGS="-w0 -msg_disable basclsnondto,unrimpret,intconlosbit $CXXFLAGS"
 fi
 
 ac_ext=cpp
diff --git a/configure.in b/configure.in
index 89416f77ad..4887df09bc 100644
--- a/configure.in
+++ b/configure.in
@@ -2139,7 +2139,7 @@ if test "x$COMPAQCXX" = "xyes"; then
     dnl intconlosbit: "conversion to integral type of smaller size could lose
     dnl               data" this is a useful warning but there are too many of
     dnl               them for now
-    CXXFLAGS="-w0 -msg_disable basclsnondto,unrimpret,intconlosbit"
+    CXXFLAGS="-w0 -msg_disable basclsnondto,unrimpret,intconlosbit $CXXFLAGS"
 fi
 
 dnl the next few tests are all for C++ features and so need to be done using