I'm closing this bug, the problem is in ctypes installer you used.

For the record: you can build a ppc/intel only version of an extension by patching the setup.py of the project your building and adding ('-arch', 'i386') or ('-arch', 'ppc') to the extra_compile_args and extra_link_args of Extension objects (I'm typing this without looking at the documention and have probably misspelled these argument names)