diff --git a/config/ompi_check_openfabrics.m4 b/config/ompi_check_openfabrics.m4
index 418a8cca27..acaff13efb 100644
--- a/config/ompi_check_openfabrics.m4
+++ b/config/ompi_check_openfabrics.m4
@@ -269,13 +269,13 @@ AC_DEFUN([OMPI_CHECK_OPENFABRICS_CM_ARGS],[
     #
     # Unconnect Datagram (UD) based connection manager
     #
-#    AC_ARG_ENABLE([openib-udcm],
-#        [AC_HELP_STRING([--enable-openib-udcm],
-#                        [Enable datagram connection support in openib BTL (default: enabled)])], 
-#                        [enable_openib_udcm="$enableval"], [enable_openib_udcm="yes"])
+    AC_ARG_ENABLE([openib-udcm],
+        [AC_HELP_STRING([--enable-openib-udcm],
+                        [Enable datagram connection support in openib BTL (default: enabled)])], 
+                        [enable_openib_udcm="$enableval"], [enable_openib_udcm="yes"])
     # Per discussion with Ralph and Nathan, disable UDCM for now.
     # It's borked and needs some surgery to get back on its feet.
-    enable_openib_udcm=no
+    # enable_openib_udcm=no
 
     #
     # Openfabrics RDMACM