Index: configure.in
===================================================================
--- configure.in	(revision 84704)
+++ configure.in	(working copy)
@@ -2685,7 +2685,7 @@
 # On Tru64, chflags seems to be present, but calling it will
 # exit Python
 AC_CACHE_CHECK([for chflags], [ac_cv_have_chflags], [dnl
-AC_RUN_IFELSE([AC_LANG_SOURCE([[[
+AC_RUN_IFELSE([AC_LANG_SOURCE([[
 #include <sys/stat.h>
 #include <unistd.h>
 int main(int argc, char*argv[])
@@ -2694,7 +2694,7 @@
     return 1;
   return 0;
 }
-]]])],
+]])],
 [ac_cv_have_chflags=yes],
 [ac_cv_have_chflags=no],
 [ac_cv_have_chflags=cross])
@@ -2703,11 +2703,11 @@
   AC_CHECK_FUNC([chflags], [ac_cv_have_chflags="yes"], [ac_cv_have_chflags="no"])
 fi
 if test "$ac_cv_have_chflags" = yes ; then
-  AC_DEFINE(HAVE_CHFLAGS, 1, [Define to 1 if you have the `chflags' function.])
+  AC_DEFINE(HAVE_CHFLAGS, 1, [Define to 1 if you have the 'chflags' function.])
 fi
 
 AC_CACHE_CHECK([for lchflags], [ac_cv_have_lchflags], [dnl
-AC_RUN_IFELSE([AC_LANG_SOURCE([[[
+AC_RUN_IFELSE([AC_LANG_SOURCE([[
 #include <sys/stat.h>
 #include <unistd.h>
 int main(int argc, char*argv[])
@@ -2716,15 +2716,26 @@
     return 1;
   return 0;
 }
-]]])],[ac_cv_have_lchflags=yes],[ac_cv_have_lchflags=no],[ac_cv_have_lchflags=cross])
+]])],[ac_cv_have_lchflags=yes],[ac_cv_have_lchflags=no],[ac_cv_have_lchflags=cross])
 ])
 if test "$ac_cv_have_lchflags" = cross ; then
   AC_CHECK_FUNC([lchflags], [ac_cv_have_lchflags="yes"], [ac_cv_have_lchflags="no"])
 fi
 if test "$ac_cv_have_lchflags" = yes ; then
-  AC_DEFINE(HAVE_LCHFLAGS, 1, [Define to 1 if you have the `lchflags' function.])
+  AC_DEFINE(HAVE_LCHFLAGS, 1, [Define to 1 if you have the 'lchflags' function.])
 fi
 
+# Check for conditionally available flags that can be passed to the *chflags(2)
+# functions, as FreeBSD defines some flags, and OSX defines others.
+if test "$ac_cv_have_chflags" = yes || test "$ac_cv_have_lchflags" = yes ; then
+  for i in UF_NOUNLINK UF_HIDDEN SF_NOUNLINK ; do
+    AC_CHECK_DECL($i,,,[[
+#include <sys/stat.h>
+#include <unistd.h>
+]])
+  done
+fi
+
 dnl Check if system zlib has *Copy() functions
 dnl
 dnl On MacOSX the linker will search for dylibs on the entire linker path
Index: Modules/posixmodule.c
===================================================================
--- Modules/posixmodule.c	(revision 84704)
+++ Modules/posixmodule.c	(working copy)
@@ -8297,6 +8297,33 @@
 #endif
 #endif
 
+#if defined(HAVE_CHFLAGS) || defined(HAVE_LCHFLAGS)
+    if (ins(d, "UF_NODUMP", (long)UF_NODUMP)) return -1;
+    if (ins(d, "UF_IMMUTABLE", (long)UF_IMMUTABLE)) return -1;
+    if (ins(d, "UF_APPEND", (long)UF_APPEND)) return -1;
+/* FreeBSD specific */
+#ifdef HAVE_UF_NOUNLINK
+    if (ins(d, "UF_NOUNLINK", (long)UF_NOUNLINK)) return -1;
+#endif
+/* OSX specific */
+#ifdef HAVE_UF_HIDDEN
+    if (ins(d, "UF_HIDDEN", (long)UF_HIDDEN)) return -1;
+#endif
+    if (ins(d, "UF_OPAQUE", (long)UF_OPAQUE)) return -1;
+    if (ins(d, "SF_ARCHIVED", (long)SF_ARCHIVED)) return -1;
+    if (ins(d, "SF_IMMUTABLE", (long)SF_IMMUTABLE)) return -1;
+    if (ins(d, "SF_APPEND", (long)SF_APPEND)) return -1;
+/* FreeBSD specific */
+#ifdef HAVE_SF_NOUNLINK
+    if (ins(d, "SF_NOUNLINK", (long)SF_NOUNLINK)) return -1;
+#endif
+/* 
+ * SF_SNAPSHOT isn't listed here because it's purely FreeBSD based, and it
+ * seems to have little value for python, as it's used by the system (kernel?)
+ * to set the snapshot inode for UFS* based filesystems.
+ */
+#endif /* defined(HAVE_CHFLAGS) || defined(HAVE_LCHFLAGS) */
+
 #if defined(PYOS_OS2)
     if (insertvalues(d)) return -1;
 #endif