multiprocessing and freezing on Windows

[SK]

To add a bit more information, I found that I needed to patch
get_command_line in multiprocessing/forking.py replacing:

        if getattr(sys, 'frozen', False):
            return [sys.executable, '--multiprocessing-fork']
        else:
            prog = 'from multiprocessing.forking import main; main()'
            return [_python_exe, '-c', prog, '--multiprocessing-fork']

with:

        if WINEXE:
            prog = 'from multiprocessing.forking import main; main()'
            return [_python_exe, '-c', prog, '--multiprocessing-fork']
        elif getattr(sys, 'frozen', False):
            return [sys.executable, '--multiprocessing-fork']
        else:
            prog = 'from multiprocessing.forking import main; main()'
            return [_python_exe, '-c', prog, '--multiprocessing-fork']

and then using py2exe I can get a working "frozen" package if I
include pythonw.exe and a subset of Python's Lib directory in my
package and call multiprocessing.set_executable to point to that
pythonw.exe.

Does the above patch address a real bug?

Is packaging with multiprocessing supposed to be this hard? If so,
some documentation is needed.