diff --git a/config/opal_mca.m4 b/config/opal_mca.m4
index e8be7ca9f4d..c0df8ed85d1 100644
--- a/config/opal_mca.m4
+++ b/config/opal_mca.m4
@@ -68,7 +68,8 @@ AC_DEFUN([OPAL_MCA],[
                         type-component pairs that will be built as
                         run-time loadable components (as opposed to
                         statically linked in), if supported on this
-                        platform.])])
+                        platform.])],
+                        [], [enable_mca_dso=btl-ugni,rcache-udreg])
     AC_ARG_ENABLE([mca-static],
         [AS_HELP_STRING([--enable-mca-static=LIST],
                        [Comma-separated list of types and/or