diff -r 8a8642e45433 src/org/python/core/PyObjectDerived.java
--- a/src/org/python/core/PyObjectDerived.java	Sun Sep 04 16:39:47 2011 -0700
+++ b/src/org/python/core/PyObjectDerived.java	Wed Sep 07 09:54:03 2011 -0400
@@ -1082,8 +1082,11 @@
         // Otherwise, we call the derived __tojava__, if it exists:
         PyType self_type=getType();
         PyObject impl=self_type.lookup("__tojava__");
-        if (impl!=null)
-            return impl.__get__(this,self_type).__call__(Py.java2py(c)).__tojava__(Object.class);
+        if (impl!=null) {
+            PyObject delegate = impl.__get__(this,self_type).__call__(Py.java2py(c));
+            if (delegate != this)
+                return delegate.__tojava__(Object.class);
+        }
         return super.__tojava__(c);
     }