Stop causing an exception when there is no AuthenticationException to ApplicationEvent mapping. Requested by Brian Moseley on acegisecurity-developer 10 November 2005.

core/src/main/java/org/acegisecurity/providers/ProviderManager.java

@@ -295,10 +295,14 @@ public class ProviderManager extends AbstractAuthenticationManager
             catch (InvocationTargetException ignored) {}
         }
 
-        Assert.notNull(event,
-            "A valid event must be available for the exception "
-            + lastException.getClass().getName());
+        if (event != null) {
             applicationEventPublisher.publishEvent(event);
+        } else {
+            if (logger.isDebugEnabled()) {
+                logger.debug("No event was found for the exception "
+                    + lastException.getClass().getName());
+            }
+        }
 
         // Throw the exception
         throw lastException;