Index: api11/src/java/javax/jdo/spi/I18NHelper.java
===================================================================
--- api11/src/java/javax/jdo/spi/I18NHelper.java	(revision 307339)
+++ api11/src/java/javax/jdo/spi/I18NHelper.java	(working copy)
@@ -236,7 +236,13 @@
 
         if (messages == null) //not found as loaded - add
         {
-            messages = ResourceBundle.getBundle(bundleName, locale, loader);
+            if (loader != null) {
+                messages = ResourceBundle.getBundle(bundleName, locale, loader);
+            } else {
+                // the JDO library is loaded by the boostrap class loader
+                messages = ResourceBundle.getBundle(bundleName, locale,
+                        getSystemClassLoaderPrivileged());
+            }
             bundles.put(bundleName, messages);
         }
         return messages;
@@ -375,4 +381,18 @@
         final int index = className.lastIndexOf('.');
         return ((index != -1) ? className.substring(0, index) : ""); // NOI18N
     }
+
+    /**
+     * Get the system class loader. This must be done in a doPrivileged 
+     * block because of security.
+     */
+    private static ClassLoader getSystemClassLoaderPrivileged() {
+        return (ClassLoader) AccessController.doPrivileged (
+            new PrivilegedAction () {
+                public Object run () {
+                    return ClassLoader.getSystemClassLoader();
+                }
+            }
+        );
+    }
 }
Index: api20/src/java/javax/jdo/spi/I18NHelper.java
===================================================================
--- api20/src/java/javax/jdo/spi/I18NHelper.java	(revision 307339)
+++ api20/src/java/javax/jdo/spi/I18NHelper.java	(working copy)
@@ -236,7 +236,13 @@
 
         if (messages == null) //not found as loaded - add
         {
-            messages = ResourceBundle.getBundle(bundleName, locale, loader);
+            if (loader != null) {
+                messages = ResourceBundle.getBundle(bundleName, locale, loader);
+            } else {
+                // the JDO library is loaded by the boostrap class loader
+                messages = ResourceBundle.getBundle(bundleName, locale,
+                        getSystemClassLoaderPrivileged());
+            }
             bundles.put(bundleName, messages);
         }
         return messages;
@@ -375,4 +381,18 @@
         final int index = className.lastIndexOf('.');
         return ((index != -1) ? className.substring(0, index) : ""); // NOI18N
     }
+
+    /**
+     * Get the system class loader. This must be done in a doPrivileged 
+     * block because of security.
+     */
+    private static ClassLoader getSystemClassLoaderPrivileged() {
+        return (ClassLoader) AccessController.doPrivileged (
+            new PrivilegedAction () {
+                public Object run () {
+                    return ClassLoader.getSystemClassLoader();
+                }
+            }
+        );
+    }
 }