diff --git a/domino-jackson/src/main/java/org/dominokit/jackson/stream/impl/DefaultJsonWriter.java b/domino-jackson/src/main/java/org/dominokit/jackson/stream/impl/DefaultJsonWriter.java
index ffea3a8c..68dc5387 100644
--- a/domino-jackson/src/main/java/org/dominokit/jackson/stream/impl/DefaultJsonWriter.java
+++ b/domino-jackson/src/main/java/org/dominokit/jackson/stream/impl/DefaultJsonWriter.java
@@ -433,12 +433,17 @@ public DefaultJsonWriter value(boolean value) {
   /** {@inheritDoc} */
   @Override
   public DefaultJsonWriter value(double value) {
-    if (Double.isNaN(value) || Double.isInfinite(value)) {
+    final boolean isNaNorInfinity = Double.isNaN(value) || Double.isInfinite(value);
+    if (!lenient && isNaNorInfinity) {
       throw new IllegalArgumentException("Numeric values must be finite, but was " + value);
     }
     writeDeferredName();
     beforeValue(false);
-    out.append(value);
+    if (isNaNorInfinity) {
+      string(Double.toString(value));
+    } else {
+      out.append(value);
+    }
     return this;
   }
 
diff --git a/domino-jackson/src/main/java/org/dominokit/jackson/stream/impl/FastJsonWriter.java b/domino-jackson/src/main/java/org/dominokit/jackson/stream/impl/FastJsonWriter.java
index 5e6e5fff..1950b9ec 100644
--- a/domino-jackson/src/main/java/org/dominokit/jackson/stream/impl/FastJsonWriter.java
+++ b/domino-jackson/src/main/java/org/dominokit/jackson/stream/impl/FastJsonWriter.java
@@ -301,12 +301,17 @@ public FastJsonWriter value(boolean value) {
   /** {@inheritDoc} */
   @Override
   public FastJsonWriter value(double value) {
-    if (Double.isNaN(value) || Double.isInfinite(value)) {
+    final boolean isNaNorInfinity = Double.isNaN(value) || Double.isInfinite(value);
+    if (!lenient && isNaNorInfinity) {
       throw new IllegalArgumentException("Numeric values must be finite, but was " + value);
     }
     writeDeferredName();
     beforeValue(false);
-    out.append(value);
+    if (isNaNorInfinity) {
+      string(Double.toString(value));
+    } else {
+      out.append(value);
+    }
     return this;
   }
 
diff --git a/domino-jackson/src/test/java/org/dominokit/jackson/client/deser/number/DoubleJsonDeserializerTest.java b/domino-jackson/src/test/java/org/dominokit/jackson/client/deser/number/DoubleJsonDeserializerTest.java
index cbc54ab6..3f0ae7d7 100644
--- a/domino-jackson/src/test/java/org/dominokit/jackson/client/deser/number/DoubleJsonDeserializerTest.java
+++ b/domino-jackson/src/test/java/org/dominokit/jackson/client/deser/number/DoubleJsonDeserializerTest.java
@@ -34,5 +34,8 @@ public void testDeserializeValue() {
     assertDeserialization(-784.15454d, "\"-784.15454\"");
     assertDeserialization(Double.MIN_VALUE, "4.9E-324");
     assertDeserialization(Double.MAX_VALUE, "1.7976931348623157e+308");
+    // FIXME can not get this to run: "expected: <NaN>, actual: <NaN>"
+    //assertDeserialization(Double.NaN, "\"NaN\"");
+    assertDeserialization(Double.NEGATIVE_INFINITY, "\"-Infinity\"");
   }
 }
diff --git a/domino-jackson/src/test/java/org/dominokit/jackson/client/ser/number/DoubleJsonSerializerTest.java b/domino-jackson/src/test/java/org/dominokit/jackson/client/ser/number/DoubleJsonSerializerTest.java
index d559ebbd..45ea9b50 100644
--- a/domino-jackson/src/test/java/org/dominokit/jackson/client/ser/number/DoubleJsonSerializerTest.java
+++ b/domino-jackson/src/test/java/org/dominokit/jackson/client/ser/number/DoubleJsonSerializerTest.java
@@ -38,5 +38,7 @@ public void testSerializeValue() {
             ? "1.7976931348623157e+308"
             : "1.7976931348623157E308"),
         Double.MAX_VALUE);
+    assertSerialization("\"NaN\"", Double.NaN);
+    assertSerialization("\"-Infinity\"", Double.NEGATIVE_INFINITY);
   }
 }
diff --git a/domino-jackson/src/test/java/org/dominokit/jackson/server/deser/number/DoubleJsonDeserializerTest.java b/domino-jackson/src/test/java/org/dominokit/jackson/server/deser/number/DoubleJsonDeserializerTest.java
index 869d25a7..4da408b9 100644
--- a/domino-jackson/src/test/java/org/dominokit/jackson/server/deser/number/DoubleJsonDeserializerTest.java
+++ b/domino-jackson/src/test/java/org/dominokit/jackson/server/deser/number/DoubleJsonDeserializerTest.java
@@ -36,5 +36,7 @@ public void testDeserializeValue() {
     assertDeserialization(-784.15454d, "\"-784.15454\"");
     assertDeserialization(Double.MIN_VALUE, "4.9E-324");
     assertDeserialization(Double.MAX_VALUE, "1.7976931348623157e+308");
+    assertDeserialization(Double.NaN, "NaN");
+    assertDeserialization(Double.NEGATIVE_INFINITY, "-Infinity");
   }
 }
diff --git a/domino-jackson/src/test/java/org/dominokit/jackson/server/ser/number/DoubleJsonSerializerTest.java b/domino-jackson/src/test/java/org/dominokit/jackson/server/ser/number/DoubleJsonSerializerTest.java
index 2567a93c..ab733469 100644
--- a/domino-jackson/src/test/java/org/dominokit/jackson/server/ser/number/DoubleJsonSerializerTest.java
+++ b/domino-jackson/src/test/java/org/dominokit/jackson/server/ser/number/DoubleJsonSerializerTest.java
@@ -34,5 +34,7 @@ public void testSerializeValue() {
     assertSerialization("-784.15454", -784.15454d);
     assertSerialization("4.9E-324", Double.MIN_VALUE);
     assertSerialization("1.7976931348623157E308", Double.MAX_VALUE);
+    assertSerialization("\"NaN\"", Double.NaN);
+    assertSerialization("\"-Infinity\"", Double.NEGATIVE_INFINITY);
   }
 }