diff --git a/src/documentation/content/xdocs/status.xml b/src/documentation/content/xdocs/status.xml
index 139ea60030..1180c5cdfc 100644
--- a/src/documentation/content/xdocs/status.xml
+++ b/src/documentation/content/xdocs/status.xml
@@ -34,6 +34,7 @@
 
     <changes>
         <release version="3.9-beta1" date="2012-??-??">
+          <action dev="poi-developers" type="fix">53974 - Avoid NPE when constructing HSSFWorbook on Google App Engine</action>
           <action dev="poi-developers" type="fix">53568 - Fixed null returned by XSSFPicture.getPictureData()</action>
           <action dev="poi-developers" type="fix">53950 - fixed setForceFormulaRecalculation to reset workbook-level "manual" flag</action>
           <action dev="poi-developers" type="fix">52211 - avoid unnessary re-coverting content types to US-ASCII, it can cause exceptions on ibm mainframes</action>
diff --git a/src/java/org/apache/poi/hssf/model/InternalWorkbook.java b/src/java/org/apache/poi/hssf/model/InternalWorkbook.java
index 3f421d99b6..7161e48f14 100644
--- a/src/java/org/apache/poi/hssf/model/InternalWorkbook.java
+++ b/src/java/org/apache/poi/hssf/model/InternalWorkbook.java
@@ -1094,12 +1094,17 @@ public final class InternalWorkbook {
     private static WriteAccessRecord createWriteAccess() {
         WriteAccessRecord retval = new WriteAccessRecord();
 
+        String defaultUserName = "POI";
         try {
-            retval.setUsername(System.getProperty("user.name"));
+            String username = System.getProperty("user.name");
+            // Google App engine returns null for user.name, see Bug 53974
+            if(username == null) username = defaultUserName;
+
+            retval.setUsername(username);
         } catch (AccessControlException e) {
                 // AccessControlException can occur in a restricted context
                 // (client applet/jws application or restricted security server)
-                retval.setUsername("POI");
+                retval.setUsername(defaultUserName);
         }
         return retval;
     }