diff --git a/m4/jm-mktime.m4 b/m4/jm-mktime.m4
index ab78db707..360e44aa3 100644
--- a/m4/jm-mktime.m4
+++ b/m4/jm-mktime.m4
@@ -8,6 +8,10 @@ dnl   #undef mktime
 dnl
 AC_DEFUN(jm_FUNC_MKTIME,
 [AC_REQUIRE([AM_FUNC_MKTIME])dnl
+
+ dnl mktime.c uses localtime_r if it exists.  Check for it.
+ AC_CHECK_FUNCS(localtime_r)
+
  if test $am_cv_func_working_mktime = no; then
    AC_DEFINE_UNQUOTED(mktime, rpl_mktime)
  fi