diff --git a/m4/ax_cflags_warn_all.m4 b/m4/ax_cflags_warn_all.m4
index 0fa3e18..1f07799 100644
--- a/m4/ax_cflags_warn_all.m4
+++ b/m4/ax_cflags_warn_all.m4
@@ -58,7 +58,7 @@
 #   modified version of the Autoconf Macro, you may extend this special
 #   exception to the GPL to apply to your modified version as well.
 
-#serial 14
+#serial 15
 
 AC_DEFUN([AX_FLAGS_WARN_ALL],[dnl
 AS_VAR_PUSHDEF([FLAGS],[_AC_LANG_PREFIX[]FLAGS])dnl
@@ -84,7 +84,7 @@ done
 FLAGS="$ac_save_[]FLAGS"
 ])
 AS_VAR_POPDEF([FLAGS])dnl
-AC_REQUIRE([AX_APPEND_FLAG])
+AX_REQUIRE_DEFINED([AX_APPEND_FLAG])
 case ".$VAR" in
      .ok|.ok,*) m4_ifvaln($3,$3) ;;
    .|.no|.no,*) m4_default($4,[m4_ifval($2,[AX_APPEND_FLAG([$2], [$1])])]) ;;
diff --git a/m4/ax_with_curses.m4 b/m4/ax_with_curses.m4
index 33a37ac..e4cbd31 100644
--- a/m4/ax_with_curses.m4
+++ b/m4/ax_with_curses.m4
@@ -88,7 +88,7 @@
 #
 #     AX_WITH_CURSES
 #     if test "x$ax_cv_ncursesw" != xyes && test "x$ax_cv_ncurses" != xyes; then
-#         AX_MSG_ERROR([requires either NcursesW or Ncurses library])
+#         AC_MSG_ERROR([requires either NcursesW or Ncurses library])
 #     fi
 #
 #   If any Curses library will do (but one must be present and must support
@@ -182,7 +182,7 @@
 #   modified version of the Autoconf Macro, you may extend this special
 #   exception to the GPL to apply to your modified version as well.
 
-#serial 13
+#serial 15
 
 AU_ALIAS([MP_WITH_CURSES], [AX_WITH_CURSES])
 AC_DEFUN([AX_WITH_CURSES], [