Don't define _XOPEN_SOURCE and _POSIX_C_SOURCE on FreeBSD 5.0. Fixes #636318.
diff --git a/configure b/configure
index 0638270..2b8b404 100755
--- a/configure
+++ b/configure
@@ -1,5 +1,5 @@
 #! /bin/sh
-# From configure.in Revision: 1.367 .
+# From configure.in Revision: 1.368 .
 # Guess values for system-dependent variables and create Makefiles.
 # Generated by GNU Autoconf 2.53 for python 2.3.
 #
@@ -1252,28 +1252,8 @@
 _ACEOF
 
 
-# The definition of _GNU_SOURCE potentially causes a change of the value
-# of _XOPEN_SOURCE. So define it only conditionally.
-
-
-
 define_xopen_source=yes
 
-# On Tru64 Unix 4.0F, defining _XOPEN_SOURCE also requires definition
-# of _XOPEN_SOURCE_EXTENDED and _POSIX_C_SOURCE, or else several APIs
-# are not declared. Since this is also needed in some cases for HP-UX,
-# we define it globally.
-
-cat >>confdefs.h <<\_ACEOF
-#define _XOPEN_SOURCE_EXTENDED 1
-_ACEOF
-
-
-cat >>confdefs.h <<\_ACEOF
-#define _POSIX_C_SOURCE 199506L
-_ACEOF
-
-
 # Arguments passed to configure.
 
 CONFIG_ARGS="$ac_configure_args"
@@ -1361,14 +1341,36 @@
   # even though select is a POSIX function. Reported by J. Ribbens.
   OpenBSD/2.* | OpenBSD/3.[012])
     define_xopen_source=no;;
+  # On FreeBSD 5.0, chroot and setgroups are not declared if _XOPEN_SOURCE
+  # is define. Reported by M. Recht.
+  FreeBSD/5.0*)
+    define_xopen_source=no;;
 esac
 
 if test $define_xopen_source = yes
 then
-  cat >>confdefs.h <<\_ACEOF
-#define _XOPEN_SOURCE 500
+
+cat >>confdefs.h <<\_ACEOF
+#define _XOPEN_SOURCE 600
 _ACEOF
 
+
+  # On Tru64 Unix 4.0F, defining _XOPEN_SOURCE also requires
+  # definition of _XOPEN_SOURCE_EXTENDED and _POSIX_C_SOURCE, or else
+  # several APIs are not declared. Since this is also needed in some
+  # cases for HP-UX, we define it globally.
+
+
+cat >>confdefs.h <<\_ACEOF
+#define _XOPEN_SOURCE_EXTENDED 1
+_ACEOF
+
+
+cat >>confdefs.h <<\_ACEOF
+#define _POSIX_C_SOURCE 200112L
+_ACEOF
+
+
 fi
 
 #