Index: src/org/python/core/PySystemState.java
===================================================================
--- src/org/python/core/PySystemState.java	(revision 6797)
+++ src/org/python/core/PySystemState.java	(working copy)
@@ -1224,6 +1224,10 @@
                 tb == null ? Py.None : tb);
     }
 
+    public String java_trace(PyObject value) {
+        return Py.getJavaExceptionTrace(value);
+    }
+
     public static void exc_clear() {
         Py.getThreadState().exception = null;
     }
Index: src/org/python/core/Py.java
===================================================================
--- src/org/python/core/Py.java	(revision 6797)
+++ src/org/python/core/Py.java	(working copy)
@@ -995,6 +995,20 @@
         ts.exception = null;
     }
 
+    /* Bug 1435: Adding a method to expose java stack trace. This code is
+     * copied from displayException() below. 
+     */
+    public static String getJavaExceptionTrace(PyObject value) {
+        if (value.getJavaProxy() != null) {
+            Object javaError = value.__tojava__(Throwable.class);
+            
+            if (javaError != null && javaError != Py.NoConversion) {
+                return getStackTrace((Throwable) javaError);
+            }
+        }
+        return null;
+    }
+
     public static void displayException(PyObject type, PyObject value, PyObject tb,
                                         PyObject file) {
         StdoutWrapper stderr = Py.stderr;
--- CPythonLib/traceback.py	2009-07-29 11:40:00.000000000 -0400
+++ dist/Lib/traceback.py	2009-09-14 14:00:52.000000000 -0400
@@ -206,7 +206,11 @@
     if value is None or not valuestr:
         line = "%s\n" % etype
     else:
-        line = "%s: %s\n" % (etype, valuestr)
+        java_trace = sys.java_trace(value)
+        if java_trace is not None:
+            line = "%s\n%s: %s\n" % (java_trace, etype, valuestr)
+        else:
+            line = "%s: %s\n" % (etype, valuestr)
     return line
 
 def _some_str(value):