Two unrelated changes:

- add test for strptime (not used by the core but needed by Marc Lemburg's
Date object).

- Test for GNU ld on Solaris; need to add an extra linker option to
export symbols in that case.
diff --git a/config.h.in b/config.h.in
index 382c46d..7c7d13c 100644
--- a/config.h.in
+++ b/config.h.in
@@ -280,6 +280,9 @@
 /* Define if you have the strftime function.  */
 #undef HAVE_STRFTIME
 
+/* Define if you have the strptime function.  */
+#undef HAVE_STRPTIME
+
 /* Define if you have the symlink function.  */
 #undef HAVE_SYMLINK