Index: test/java/javax/jdo/identity/ObjectIdentityTest.java
===================================================================
--- test/java/javax/jdo/identity/ObjectIdentityTest.java	(revision 582405)
+++ test/java/javax/jdo/identity/ObjectIdentityTest.java	(working copy)
@@ -237,6 +237,14 @@
             "java.util.Date:" + rightNow);
     }
 
+    public void testStringNullDateConstructor() {
+        // this test uses the standard date-time format
+        // "M/d/yy h:mm a"
+        helper.registerDateFormat(DateFormat.getInstance());
+        Object c1 = new ObjectIdentity(Object.class, 
+            "java.util.Date:" + "10/9/2007 4:26 PM");
+    }
+
     public void testBadStringDateConstructor() {
         try {
             ObjectIdentity c1 = new ObjectIdentity(Object.class, 
Index: src/java/javax/jdo/spi/JDOImplHelper.java
===================================================================
--- src/java/javax/jdo/spi/JDOImplHelper.java	(revision 582408)
+++ src/java/javax/jdo/spi/JDOImplHelper.java	(working copy)
@@ -26,6 +26,9 @@
 
 import java.lang.reflect.Constructor;
 
+import java.security.AccessController;
+import java.security.PrivilegedAction;
+
 import java.text.DateFormat;
 import java.text.ParsePosition;
 import java.text.SimpleDateFormat;
@@ -120,7 +123,7 @@
     /** Register the default DateFormat instance.
      */
     static {
-        jdoImplHelper.registerDateFormat(DateFormat.getDateTimeInstance());
+        jdoImplHelper.registerDateFormat(getDateTimeInstance());
     }
     
     /** Creates new JDOImplHelper */
@@ -794,10 +797,39 @@
     }
 
     /**
+     * Get the DateFormat instance for the default locale from the VM.
+     * This requires the following privileges for JDOImplHelper in the
+     * security permissions file:
+     * permission java.util.PropertyPermission "user.country", "read";
+     * permission java.util.PropertyPermission "user.timezone", "read,write";
+     * permission java.util.PropertyPermission "java.home", "read";
+     * If these permissions are not present, or there is some other
+     * problem getting the default date format, a simple formatter is returned.
+     * @since 2.1
+     * @return the default date-time formatter
+     */
+    static DateFormat getDateTimeInstance() {
+        DateFormat result = null;
+        try {
+        result = (DateFormat) AccessController.doPrivileged (
+            new PrivilegedAction () {
+                public Object run () {
+                    return DateFormat.getDateTimeInstance();
+                }
+            }
+            );
+        } catch (Exception ex) {
+            result = DateFormat.getInstance();
+        }
+        return result;
+    }
+
+    /**
      * Register a DateFormat instance for use with constructing Date 
      * instances. The default is the default DateFormat instance.
      * If the new instance implements SimpleDateFormat, get its pattern
      * for error messages.
+     * @since 2.0
      * @param df the DateFormat instance to use
      */
     public synchronized void registerDateFormat(DateFormat df) {