diff --git a/security/src/main/java/org/springframework/ws/soap/security/xwss/callback/DefaultTimestampValidator.java b/security/src/main/java/org/springframework/ws/soap/security/xwss/callback/DefaultTimestampValidator.java
index d1e196b6..e4adc4af 100644
--- a/security/src/main/java/org/springframework/ws/soap/security/xwss/callback/DefaultTimestampValidator.java
+++ b/security/src/main/java/org/springframework/ws/soap/security/xwss/callback/DefaultTimestampValidator.java
@@ -36,13 +36,13 @@ public class DefaultTimestampValidator implements TimestampValidationCallback.Ti
             throws TimestampValidationCallback.TimestampValidationException {
         if (request instanceof TimestampValidationCallback.UTCTimestampRequest) {
             TimestampValidationCallback.UTCTimestampRequest utcRequest =
-                    ((TimestampValidationCallback.UTCTimestampRequest) request);
+                    (TimestampValidationCallback.UTCTimestampRequest) request;
             Date created = parseDate(utcRequest.getCreated());
-            Date expired = parseDate(utcRequest.getExpired());
 
             validateCreationTime(created, utcRequest.getMaxClockSkew(), utcRequest.getTimestampFreshnessLimit());
 
-            if (expired != null) {
+            if (utcRequest.getExpired() != null) {
+                Date expired = parseDate(utcRequest.getExpired());
                 validateExpirationTime(expired, utcRequest.getMaxClockSkew());
             }
         }
diff --git a/security/src/test/java/org/springframework/ws/soap/security/xwss/callback/DefaultTimestampValidatorTest.java b/security/src/test/java/org/springframework/ws/soap/security/xwss/callback/DefaultTimestampValidatorTest.java
new file mode 100644
index 00000000..e0a40606
--- /dev/null
+++ b/security/src/test/java/org/springframework/ws/soap/security/xwss/callback/DefaultTimestampValidatorTest.java
@@ -0,0 +1,25 @@
+package org.springframework.ws.soap.security.xwss.callback;
+
+import com.sun.xml.wss.impl.callback.TimestampValidationCallback;
+import junit.framework.TestCase;
+
+public class DefaultTimestampValidatorTest extends TestCase {
+
+    private DefaultTimestampValidator validator;
+
+    protected void setUp() throws Exception {
+        validator = new DefaultTimestampValidator();
+    }
+
+    public void testValidate() throws Exception {
+        TimestampValidationCallback.Request request = new TimestampValidationCallback.UTCTimestampRequest(
+                "2006-09-25T20:42:50Z", "2107-09-25T20:42:50Z", 100, Long.MAX_VALUE);
+        validator.validate(request);
+    }
+
+    public void testValidateNoExpired() throws Exception {
+        TimestampValidationCallback.Request request =
+                new TimestampValidationCallback.UTCTimestampRequest("2006-09-25T20:42:50Z", null, 100, Long.MAX_VALUE);
+        validator.validate(request);
+    }
+}
\ No newline at end of file