HAPI FHIR Instance Validator fails resource loading with Java Modules

Question

I am trying to get the Instance Validator to work within a Java project which uses Java Modules.

I try to execute the following example: https://hapifhir.io/hapi-fhir/docs/validation/instance_validator.html

I have the following dependencies:

    <dependency>
        <groupId>ca.uhn.hapi.fhir</groupId>
        <artifactId>hapi-fhir-validation</artifactId>
        <version>6.10.0</version>
    </dependency>
    <dependency>
        <groupId>ca.uhn.hapi.fhir</groupId>
        <artifactId>hapi-fhir-structures-r4</artifactId>
        <version>6.10.0</version>
    </dependency>
    <dependency>
        <groupId>ca.uhn.hapi.fhir</groupId>
        <artifactId>hapi-fhir-validation-resources-r4</artifactId>
        <version>6.10.0</version>
    </dependency>

However, the Validator is unable to load the (xml) resources, which are required to validate a resource (in the example: Patient). There seems to be a class loading issue but I couldn't pin it down. The culprit is DefaultProfileValidationSupportBundleStrategy#loadStructureDefinitions in line 380. The resources are always null. They do not seem to be on the classpath. The resources the code tries to load are bundled in the hapi-fhir-validation-resources-r4 dependency. When I remove Java Modules support (i.e. delete module-info.java) the code works as intended (no error messages for the patient).

Did anyone have a similar issue and was able to solve it? Removing Java Modules is not an option for me. This is the content of my module-info.java:

requires org.hl7.fhir.convertors;
requires org.hl7.fhir.dstu2;
requires org.hl7.fhir.dstu2016may;
requires org.hl7.fhir.dstu3;
requires org.hl7.fhir.r4;
requires org.hl7.fhir.r4b;
requires org.hl7.fhir.r5;
requires org.hl7.fhir.utilities;
requires org.hl7.fhir.validation;
requires hapi.fhir.validation.resources.r4;

Cheers.