Revert 43615, fixing it properly through quadrigraphs.

Apparently, the code in #1416559 was not generated
through invoking autoconf.

configure

 #! /bin/sh
-# From configure.in Revision: 43604 .
+# From configure.in Revision: 43615 .
 # Guess values for system-dependent variables and create Makefiles.
 # Generated by GNU Autoconf 2.59 for python 2.5.
 #
@@ -1511,18 +1511,14 @@ case $ac_sys_system/$ac_sys_release in
       define_xopen_source=no
     fi
     ;;
-  # XXX(nnorwitz): the 2 cases below should be Darwin/[78].*,
-  # but autoconf seems to convert that to Darwin/78.* which is incorrect.
-  # On Mac OS X 10.3, defining _POSIX_C_SOURCE or _XOPEN_SOURCE
-  # has no effect, don't bother defining them.
-  Darwin/7.*)
-    define_xopen_source=no
-    ;;
   # On Mac OS X 10.4, defining _POSIX_C_SOURCE or _XOPEN_SOURCE
   # disables platform specific features beyond repair.
-  Darwin/8.*)
+  # On Mac OS X 10.3, defining _POSIX_C_SOURCE or _XOPEN_SOURCE
+  # has no effect, don't bother defineing them
+  Darwin/[78].*)
     define_xopen_source=no
     ;;
+
 esac
 
 if test $define_xopen_source = yes

configure.in

@@ -171,18 +171,14 @@ case $ac_sys_system/$ac_sys_release in
       define_xopen_source=no
     fi
     ;;
-  # XXX(nnorwitz): the 2 cases below should be Darwin/[78].*, 
-  # but autoconf seems to convert that to Darwin/78.* which is incorrect.
-  # On Mac OS X 10.3, defining _POSIX_C_SOURCE or _XOPEN_SOURCE 
-  # has no effect, don't bother defining them.
-  Darwin/7.*)
-    define_xopen_source=no
-    ;;
   # On Mac OS X 10.4, defining _POSIX_C_SOURCE or _XOPEN_SOURCE
   # disables platform specific features beyond repair.
-  Darwin/8.*)
+  # On Mac OS X 10.3, defining _POSIX_C_SOURCE or _XOPEN_SOURCE 
+  # has no effect, don't bother defineing them
+  Darwin/@<:@78@:>@.*)
     define_xopen_source=no
     ;;
+
 esac
 
 if test $define_xopen_source = yes