diff --git a/config/ompi_mca.m4 b/config/ompi_mca.m4
index 1945e9df4c..62ff400338 100644
--- a/config/ompi_mca.m4
+++ b/config/ompi_mca.m4
@@ -550,8 +550,16 @@ AC_DEFUN([MCA_CONFIGURE_M4_CONFIG_COMPONENT],[
     # try to configure the component.  pay no attention to
     # --enable-dist, since we'll always have makefiles.
     AS_IF([test "$should_build" = "1"],
-          [MCA_$2_$3_CONFIG([should_build=1], 
-                            [should_build=0])])
+          [m4_ifdef([MCA_]$2[_]$3[_CONFIG],
+                    [MCA_$2_$3_CONFIG([should_build=1], 
+                                      [should_build=0])],
+                    # If they forgot to define an MCA_<fw>_<comp>_CONFIG 
+                    # macro, print a friendly warning and abort.
+                    [AC_MSG_WARN([*** The $2:$3 did not define an])
+                     AC_MSG_WARN([*** MCA_$2_$3_CONFIG macro in the])
+                     AC_MSG_WARN([*** $1/$2/$3/configure.m4 file])
+                     AC_MSG_ERROR([Cannot continue])])
+          ])
 
     AS_IF([test "$should_build" = "1"],
           [MCA_PROCESS_COMPONENT($1, $2, $3, $4, $5, $6, $7, $compile_mode)],