diff --git a/m4/prereq.m4 b/m4/prereq.m4
index ad5e21293..b13c70231 100644
--- a/m4/prereq.m4
+++ b/m4/prereq.m4
@@ -71,6 +71,7 @@ AC_DEFUN([jm_PREREQ],
   AC_REQUIRE([gl_HASH])
   AC_REQUIRE([gl_HUMAN])
   AC_REQUIRE([gl_MBSWIDTH])
+  AC_REQUIRE([gl_MD5])
   AC_REQUIRE([gl_MEMCOLL])
   AC_REQUIRE([gl_MODECHANGE])
   AC_REQUIRE([gl_MOUNTLIST])