Import problem

[Johny]

I have this directory structure

C:
      \A
         __init__.py
         amodule.py

         \B
          __init__.py
          bmodule.py

           \D
            __init__.py
            dmodule.py

and  I want to import  bmodule.py
C:\>cd \

C:\>python
Python 2.5 (r25:51908, Sep 19 2006, 09:52:17) [MSC v.1310 32 bit
(Intel)] on win
32
Type "help", "copyright", "credits" or "license" for more information.
>>> from A.B import  bmodule
I am bmodule
>>>
C:\>

so far so good. Now I would like to import bmodule but if the current
directory is \D subdirectory.

C:> cd \A\B\D
C:\A\B\D>
C:\A\B\D>python
Python 2.5 (r25:51908, Sep 19 2006, 09:52:17) [MSC v.1310 32 bit
(Intel)] on win
32
Type "help", "copyright", "credits" or "license" for more information.
>>> import sys
>>> sys.path.append('C:\\A')
>>> from A.B import bmodule
Traceback (most recent call last):
  File "<stdin>", line 1, in <module>
ImportError: No module named A.B

C:\>

so I can not import a module from the parent directory? Or where did I
make an error?
Thanks for help

L.