SystemError: ... cellobject.c:22: bad argument to internal ?

[robert]

 From the trace of a 2.3.5 software i got:

\'SystemError:
C:\\\\sf\\\\python\\\\dist23\\\\src\\\\Objects\\\\cellobject.c:22: bad 
argument to internal
function\\n\']


from the middle of normal function / or its call. What is this?

There is:

http://mail.python.org/pipermail/python-list/2005-January/260273.html

but seems to be something else. There is no dynamic addition of 
class-method. But the last function called is a callback function  in 
3rd level inner function of class method like:

class X:
    def a():
      def b():
        ...
        def c():...            # breaks with systemerror
        schedule_callback(c)   # -> upon Windows WM_TIMER event
    ...


Will there be another bug-fix release of Python 2.3   ?

-robert