diff --git a/janos-core/src/main/java/org/apache/olingo/odata2/janos/processor/core/extension/ExtensionProcessor.java b/janos-core/src/main/java/org/apache/olingo/odata2/janos/processor/core/extension/ExtensionProcessor.java
index 1d5c60d..72be025 100644
--- a/janos-core/src/main/java/org/apache/olingo/odata2/janos/processor/core/extension/ExtensionProcessor.java
+++ b/janos-core/src/main/java/org/apache/olingo/odata2/janos/processor/core/extension/ExtensionProcessor.java
@@ -14,6 +14,7 @@
 import java.lang.reflect.InvocationTargetException;
 import java.lang.reflect.Method;
 import java.lang.reflect.Proxy;
+import java.util.ArrayList;
 import java.util.Arrays;
 
 /**
@@ -148,7 +149,11 @@ public Object invoke(Object o, Method method, Object[] objects) throws Throwable
       // XXX: change
       if (isValid(method)) {
         invokeMethod = method;
-        invokeParameters = Arrays.copyOf(objects, objects.length);
+        if (objects != null) {
+        	invokeParameters = Arrays.copyOf(objects, objects.length);
+        } else {
+        	invokeParameters = new Object[0];
+        }
       } else {
         throw new RuntimeException("Invalid class '" + method.getDeclaringClass() +
             "' can not wrapped for asynchronous processing.");