diff -ur jruby-1.4.0/src/org/jruby/java/proxies/ConcreteJavaProxy.java jruby-1.4.0-typed_null/src/org/jruby/java/proxies/ConcreteJavaProxy.java
--- jruby-1.4.0/src/org/jruby/java/proxies/ConcreteJavaProxy.java	2009-11-02 10:15:10.000000000 -0800
+++ jruby-1.4.0-typed_null/src/org/jruby/java/proxies/ConcreteJavaProxy.java	2010-01-06 15:01:52.000000000 -0800
@@ -4,6 +4,7 @@
 import org.jruby.RubyClass;
 import org.jruby.RubyModule;
 import org.jruby.internal.runtime.methods.DynamicMethod;
+import org.jruby.internal.runtime.methods.JavaMethod.JavaMethodZero;
 import org.jruby.javasupport.JavaObject;
 import org.jruby.javasupport.util.RuntimeHelpers;
 import org.jruby.runtime.Block;
@@ -28,11 +29,19 @@
             }
         });
         
-        RubyClass singleton = concreteJavaProxy.getSingletonClass();
+        final RubyClass singleton = concreteJavaProxy.getSingletonClass();
         
         final DynamicMethod oldNew = singleton.searchMethod("new");
         
         singleton.addMethod("new", new ConcreteNewMethod(singleton, Visibility.PUBLIC, oldNew));
+        singleton.addMethod("null", new JavaMethodZero(singleton, Visibility.PUBLIC) {
+            @Override
+            public IRubyObject call(ThreadContext context, IRubyObject self, RubyModule clazz, String name) {
+                IRubyObject proxy = oldNew.call(context, self, clazz, "new_proxy");
+                proxy.dataWrapStruct(JavaObject.wrap(context.getRuntime(), null));
+                return proxy;
+            }
+        });
         
         concreteJavaProxy.addMethod("initialize", new org.jruby.internal.runtime.methods.JavaMethod(concreteJavaProxy, Visibility.PUBLIC) {
             @Override
diff -ur jruby-1.4.0/src/org/jruby/javasupport/JavaClass.java jruby-1.4.0-typed_null/src/org/jruby/javasupport/JavaClass.java
--- jruby-1.4.0/src/org/jruby/javasupport/JavaClass.java	2009-11-02 10:15:10.000000000 -0800
+++ jruby-1.4.0-typed_null/src/org/jruby/javasupport/JavaClass.java	2010-01-06 15:01:52.000000000 -0800
@@ -69,6 +69,7 @@
 import org.jruby.common.IRubyWarnings.ID;
 import org.jruby.exceptions.RaiseException;
 import org.jruby.internal.runtime.methods.DynamicMethod;
+import org.jruby.internal.runtime.methods.JavaMethod.JavaMethodZero;
 import org.jruby.java.addons.ArrayJavaAddons;
 import org.jruby.java.proxies.ArrayJavaProxy;
 import org.jruby.java.invokers.ConstructorInvoker;
diff -ur jruby-1.4.0/src/org/jruby/javasupport/Java.java jruby-1.4.0-typed_null/src/org/jruby/javasupport/Java.java
--- jruby-1.4.0/src/org/jruby/javasupport/Java.java	2009-11-02 10:15:10.000000000 -0800
+++ jruby-1.4.0-typed_null/src/org/jruby/javasupport/Java.java	2010-01-06 15:01:52.000000000 -0800
@@ -468,6 +468,7 @@
             proxyClass.inherit(superClass);
         }
         proxyClass.callMethod(runtime.getCurrentContext(), "java_class=", javaClass);
+        proxyClass.dataWrapStruct(javaClass.javaClass());
         javaClass.setupProxy(proxyClass);
 
         // add java_method for unbound use
diff -ur jruby-1.4.0/src/org/jruby/javasupport/JavaProxyMethods.java jruby-1.4.0-typed_null/src/org/jruby/javasupport/JavaProxyMethods.java
--- jruby-1.4.0/src/org/jruby/javasupport/JavaProxyMethods.java	2009-11-02 10:15:10.000000000 -0800
+++ jruby-1.4.0-typed_null/src/org/jruby/javasupport/JavaProxyMethods.java	2010-01-06 15:01:52.000000000 -0800
@@ -1,6 +1,7 @@
 package org.jruby.javasupport;
 
 import org.jruby.Ruby;
+import org.jruby.RubyClass;
 import org.jruby.RubyModule;
 import org.jruby.RubyObject;
 import org.jruby.anno.JRubyMethod;
diff -ur jruby-1.4.0/src/org/jruby/RubyBasicObject.java jruby-1.4.0-typed_null/src/org/jruby/RubyBasicObject.java
--- jruby-1.4.0/src/org/jruby/RubyBasicObject.java	2009-11-02 10:15:08.000000000 -0800
+++ jruby-1.4.0-typed_null/src/org/jruby/RubyBasicObject.java	2010-01-06 15:14:37.000000000 -0800
@@ -34,6 +34,8 @@
 import java.util.concurrent.atomic.AtomicBoolean;
 
 import org.jruby.anno.JRubyMethod;
+import org.jruby.java.proxies.JavaProxy;
+import org.jruby.javasupport.JavaClass;
 import org.jruby.javasupport.JavaObject;
 import org.jruby.javasupport.JavaUtil;
 import org.jruby.javasupport.util.RuntimeHelpers;
@@ -582,10 +584,21 @@
      * translations.
      */
     public Class getJavaClass() {
+        if (this instanceof JavaProxy) {
+            RubyClass mc = getMetaClass();
+            if (mc != null)
+            {
+               Class c = (Class) mc.dataGetStruct(); 
+               if (c != null)
+                   return c;
+            }
+        }
+
         Object obj = dataGetStruct();
         if (obj instanceof JavaObject) {
             return ((JavaObject)obj).getValue().getClass();
         }
+
         return getClass();
     }