Patch #1227966: Do not defined _XOPEN_SOURCE_EXTENDED on Solaris 10.

Also set _XOPEN_SOURCE to 500.
Will backport to 2.4.

configure

@@ -1,5 +1,5 @@
 #! /bin/sh
-# From configure.in Revision: 1.486 .
+# From configure.in Revision: 39267 .
 # Guess values for system-dependent variables and create Makefiles.
 # Generated by GNU Autoconf 2.59 for python 2.5.
 #
@@ -1523,8 +1523,10 @@ if test $define_xopen_source = yes
 then
   # On Solaris w/ g++ it appears that _XOPEN_SOURCE has to be
   # defined precisely as g++ defines it
+  # Furthermore, on Solaris 10, XPG6 requires the use of a C99
+  # compiler
   case $ac_sys_system/$ac_sys_release in
-    SunOS/5.8|SunOS/5.9)
+    SunOS/5.8|SunOS/5.9|SunOS/5.10)
 
 cat >>confdefs.h <<\_ACEOF
 #define _XOPEN_SOURCE 500
@@ -1544,12 +1546,19 @@ _ACEOF
   # 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.
-
+  # except for Solaris 10, where it must not be defined,
+  # as it implies XPG4.2
+  case $ac_sys_system/$ac_sys_release in
+    SunOS/5.10)
+      ;;
+    *)
 
 cat >>confdefs.h <<\_ACEOF
 #define _XOPEN_SOURCE_EXTENDED 1
 _ACEOF
 
+      ;;
+  esac
 
 
 cat >>confdefs.h <<\_ACEOF