[Python] Embedded python 2.6 in C++ problems

Hi,

I'm extending some old Visual Studio 6 MFC code to add embedded python
scripting. It works fine most of the time but some python function calls do
not work as expected.

The C++ code is a multithreaded MFC application. I was assuming that it was
GIL issues but I have tried using the manual locking (PyEval_SaveThread &
PyEval_RestoreThread) and what seems to be the current method
(PyGILState_Ensure & PyGILState_Release)

Here's the error I'm getting:

Traceback (most recent call last):
File "...scripts\receipt_parser.py", line 296, in
get_giftcard_purchase_value
details = extract_transaction_details_section(test)
File "...scripts\receipt_parser.py", line 204, in
extract_transaction_details_section
for line in base_details:
TypeError: expected string or Unicode object, NoneType found

base_details is a string variable and the code runs fine when run from
standard interpreter. Many other function calls work fine from the embedded
app.

I create and then Py_DECREF the function parameters and the return value
after each function call. The module import is created at C++ object
constructor and then Py_DECREF'd in the desctuctor

Anyone else had issues of this kind?

Thanks,
Paul.