Hi All, I built the python-2.6.2 with the latest libffi-3.0.9 in AIX 5.3 using xlc compiler. When i try to run the ctypes test cases, two failures are seen in test_bitfields. *test_ints (ctypes.test.test_bitfields.C_Test) ... FAIL test_shorts (ctypes.test.test_bitfields.C_Test) ... FAIL* I have attached the full test case result. If i change the type c_int and c_short to c_unit and c_ushort of class "BITS(Structure)" in file test_bitfields.py then no failures are seen. Has anyone faced the similar issue or any help is appreciated. Thanks, Sangamesh