Problem with SAMR pipe (ChangePassword() Python binding)

[Zahari Zahariev]

Hello Samba4,

I am preparing a Python binding for the samr_ChangePassword() function. 
It took quite a while (usual reasons no know-how), but finally Andrew 
helped me out by taking a 'magic look' and refactoring py_net_join() in 
samba4/libbet/py_net.c.

I copied the same approach to passing credentials along but then I 
bumped across another error:

python lib/ldb/tests/python/samr-test.py <Windows_2003_AD_IP> 
-UAdministrator%old123@
test: test_samr (__main__.SamrTests)
baseDN: DC=zahari,DC=tk
['ChangePassword', 'Join', '__doc__', '__file__', '__name__']
Unable to setup messaging listener for 
'/usr/local/samba/private/smbd.tmp/messaging/msg.0.193676647.0':NT_STATUS_OBJECT_NAME_NOT_FOUND
error: test_samr (__main__.SamrTests) [
Traceback (most recent call last):
  File "lib/ldb/tests/python/samr-test.py", line 79, in test_samr
    newpassword="samba123@", level=1, credentials=creds)
RuntimeError: Connection to SAMR pipe of PDC of domain 'ZAHARI' failed: 
NT_STATUS_INVALID_PARAMETER
]
 
I am providing the patch that contains my current progress.

Regards,

    --Zahari