jpackage --add-modules cannot find additional modules with non-modular app

I have found what looks like a regression in the latest jpacakge EA build (64). To reproduce this, download the JavaFX 13 jmod files from https://openjfx.io/ and use them to package a JavaFX application (I used the Ensemble8 sample).

jpackage --package-type app-image \
    --name Ensemble \
    --dest output --input input \
    --main-jar Ensemble8.jar \
    --module-path ../javafx-jmods-13 \
    --add-modules javafx.web,javafx.media,javafx.fxml,java.logging

I get the following error, which suggests something wrong with the module path:

Module [javafx.web] does not exist
Module [javafx.fxml] does not exist
Module [javafx.media] does not exist

I tried with an absolute path to the javafx modules, but that didn't make a difference.

It worked with the previous EA build.