diff --git a/openbsc/src/libctrl/control_if.c b/openbsc/src/libctrl/control_if.c
index b31f34f..b5db31d 100644
--- a/openbsc/src/libctrl/control_if.c
+++ b/openbsc/src/libctrl/control_if.c
@@ -147,7 +147,7 @@
 	vector vline, cmdvec, cmds_vec;
 
 	ret = CTRL_CMD_ERROR;
-	cmd->reply = "Someone forgot to fill in the reply.";
+	cmd->reply = NULL;
 	node = CTRL_NODE_ROOT;
 	cmd->node = net;
 
@@ -238,6 +238,14 @@
 	cmd_free_strvec(vline);
 
 err:
+	if (!cmd->reply) {
+		LOGP(DCTRL, LOGL_ERROR, "cmd->reply has not been set.\n");
+		if (ret == CTRL_CMD_ERROR)
+			cmd->reply = "An error has occured.";
+		else
+			cmd->reply = "Command has been handled.";
+	}
+
 	if (ret == CTRL_CMD_ERROR)
 		cmd->type = CTRL_TYPE_ERROR;
 	return ret;
diff --git a/openbsc/tests/ctrl_test_runner.py b/openbsc/tests/ctrl_test_runner.py
index 24732e0..dfdec40 100644
--- a/openbsc/tests/ctrl_test_runner.py
+++ b/openbsc/tests/ctrl_test_runner.py
@@ -159,6 +159,10 @@
         self.assertEquals(r['mtype'], 'ERROR')
         self.assertEquals(r['error'], 'Command not found')
 
+        r = self.do_set('rf_locked', '999')
+        self.assertEquals(r['mtype'], 'ERROR')
+        self.assertEquals(r['error'], 'Value failed verification.')
+
         r = self.do_get('bts')
         self.assertEquals(r['mtype'], 'ERROR')
         self.assertEquals(r['error'], 'Error while parsing the index.')