Update Pyrex/swig_sources workaround for newer Pyrex versions

(backport)

--HG--
branch : setuptools-0.6
extra : convert_revision : svn%3A6015fed2-1504-0410-9fe1-9d1591cc4771/sandbox/branches/setuptools-0.6%4059983

setuptools.txt

@@ -2616,6 +2616,8 @@ Release Notes/Change History
    non-Windows platforms, due to distutils not handling manifest file line
    endings correctly.
 
+ * Updated Pyrex support to work with Pyrex 0.9.6 and higher.
+
 0.6c7
  * Fixed ``distutils.filelist.findall()`` crashing on broken symlinks, and 
    ``egg_info`` command failing on new, uncommitted SVN directories.

setuptools/command/build_ext.py

@@ -70,7 +70,7 @@ class build_ext(_build_ext):
                 self.write_stub(package_dir or os.curdir, ext, True)
 
 
-    if _build_ext is not _du_build_ext:
+    if _build_ext is not _du_build_ext and not hasattr(_build_ext,'pyrex_sources'):
         # Workaround for problems using some Pyrex versions w/SWIG and/or 2.4
         def swig_sources(self, sources, *otherargs):
             # first do any Pyrex processing