Arfrever, do you mean this patch?
http://bugs.python.org/file13897/issue5504-linux.patch

It does not cleanly apply to Gentoo's 2.6.5-r3 ebuild, neither it does apply to 2.6.5, 2.7 or 3.2.1 releases from the Python website.

Which python release/branch should it work with?

Output below:
Python-2.6.5 # patch -p0 < ../issue5504-linux.patch
patching file setup.py
Hunk #1 succeeded at 1744 (offset 23 lines).
patching file Modules/_ctypes/malloc_closure.c
Reversed (or previously applied) patch detected!  Assume -R? [n] n
Apply anyway? [n] y
Hunk #1 FAILED at 1.
File Modules/_ctypes/malloc_closure.c is not empty after patch, as expected
1 out of 1 hunk FAILED -- saving rejects to file Modules/_ctypes/malloc_closure.c.rej
patching file Modules/_ctypes/_ctypes.c
Hunk #1 succeeded at 3443 (offset 3 lines).
patching file Modules/_ctypes/libffi/fficonfig.py.in
patching file Modules/_ctypes/libffi/src/closures.c
patching file Modules/_ctypes/libffi/src/dlmalloc.c
patching file Modules/_ctypes/ctypes.h
patching file Modules/_ctypes/callbacks.c
Hunk #1 FAILED at 21.
Hunk #3 FAILED at 403.
Hunk #4 succeeded at 451 (offset 1 line).
2 out of 4 hunks FAILED -- saving rejects to file Modules/_ctypes/callbacks.c.rej

src # cd Python-2.7
Python-2.7 # patch -p0 < ../issue5504-linux.patch
patching file setup.py
Hunk #1 succeeded at 1865 (offset 144 lines).
patching file Modules/_ctypes/malloc_closure.c
Reversed (or previously applied) patch detected!  Assume -R? [n]
Apply anyway? [n] y
Hunk #1 FAILED at 1.
File Modules/_ctypes/malloc_closure.c is not empty after patch, as expected
1 out of 1 hunk FAILED -- saving rejects to file Modules/_ctypes/malloc_closure.c.rej
patching file Modules/_ctypes/_ctypes.c
Hunk #1 FAILED at 3440.
1 out of 1 hunk FAILED -- saving rejects to file Modules/_ctypes/_ctypes.c.rej
patching file Modules/_ctypes/libffi/fficonfig.py.in
patching file Modules/_ctypes/libffi/src/closures.c
patching file Modules/_ctypes/libffi/src/dlmalloc.c
patching file Modules/_ctypes/ctypes.h
Hunk #1 FAILED at 95.
1 out of 1 hunk FAILED -- saving rejects to file Modules/_ctypes/ctypes.h.rej
patching file Modules/_ctypes/callbacks.c
Hunk #1 FAILED at 21.
Hunk #2 FAILED at 373.
Hunk #3 FAILED at 403.
Hunk #4 FAILED at 450.
4 out of 4 hunks FAILED -- saving rejects to file Modules/_ctypes/callbacks.c.rej

Python-2.7 # cd ..
src # cd Python-3.1.2
Python-3.1.2 # patch -p0 < ../issue5504-linux.patch 
patching file setup.py
Hunk #1 succeeded at 1513 (offset -208 lines).
patching file Modules/_ctypes/malloc_closure.c
Reversed (or previously applied) patch detected!  Assume -R? [n] y
patching file Modules/_ctypes/_ctypes.c
Hunk #1 succeeded at 3367 (offset -73 lines).
patching file Modules/_ctypes/libffi/fficonfig.py.in
patching file Modules/_ctypes/libffi/src/closures.c
patching file Modules/_ctypes/libffi/src/dlmalloc.c
patching file Modules/_ctypes/ctypes.h
Hunk #1 succeeded at 54 (offset -41 lines).
patching file Modules/_ctypes/callbacks.c
Hunk #1 FAILED at 21.
Hunk #2 succeeded at 370 (offset -3 lines).
Hunk #3 succeeded at 401 with fuzz 2 (offset -2 lines).
Hunk #4 succeeded at 448 (offset -2 lines).
1 out of 4 hunks FAILED -- saving rejects to file Modules/_ctypes/callbacks.c.rej