diff --git a/src/java/org/apache/poi/util/LittleEndian.java b/src/java/org/apache/poi/util/LittleEndian.java
index 935fd5a668..d7cdc18426 100644
--- a/src/java/org/apache/poi/util/LittleEndian.java
+++ b/src/java/org/apache/poi/util/LittleEndian.java
@@ -386,7 +386,11 @@ public class LittleEndian
 
     public static void putDouble(final byte[] data, final int offset,
             final double value) {
-        putNumber(data, offset, Double.doubleToRawLongBits(value), DOUBLE_SIZE);
+        // Excel likes NaN to be a specific value.
+        if (Double.isNaN(value))
+            putNumber(data, offset, -276939487313920L, DOUBLE_SIZE);
+        else
+            putNumber(data, offset, Double.doubleToLongBits(value), DOUBLE_SIZE);
     }
 
 
diff --git a/src/testcases/org/apache/poi/util/TestLittleEndian.java b/src/testcases/org/apache/poi/util/TestLittleEndian.java
index 56d830cc0e..406737bdb2 100644
--- a/src/testcases/org/apache/poi/util/TestLittleEndian.java
+++ b/src/testcases/org/apache/poi/util/TestLittleEndian.java
@@ -166,9 +166,6 @@ public class TestLittleEndian
         assertEquals(_doubles[ 1 ], LittleEndian.getDouble( _double_array, LittleEndian.DOUBLE_SIZE), 0.000001);
         assertTrue(Double.isNaN(LittleEndian.getDouble(_nan_double_array)));
 
-        // does not work.  apparently nan does not always equal nan!
-        //assertEquals(_doubles[ 2 ], LittleEndian.getDouble(_nan_double_array), 0.000001);
-
         double nan = LittleEndian.getDouble(_nan_double_array);
         byte[] data = new byte[8];
         LittleEndian.putDouble(data, nan);