Validation of custom resource structures

[Poseidon]

Hello,

I've added a custom resource structure to my project, just as portrayed here: http://hapifhir.io/doc_custom_structures.html. Now when POSTing a new instance of this structure to my backend, the resource validation fails:

Validating failed:
* Location: null
* Severity: ERROR
* Message : cvc-elt.1: Deklaration des Elements 'FertilizationReport' kann nicht gefunden werden.
* Location: null
* Severity: FATAL
* Message : No profile found for resource type FertilizationReport

I tried adding Validation Support to my validator instance, but that does not seem to do the trick:

public class AHRValidationSupport implements IValidationSupport {


    @Override
    public ValueSet.ValueSetExpansionComponent expandValueSet(FhirContext theContext, ValueSet.ConceptSetComponent theInclude) {
        return null;
    }


    @Override
    public ValueSet fetchCodeSystem(FhirContext theContext, String theSystem) {
        return null;
    }


    @Override
    public <T extends IBaseResource> T fetchResource(FhirContext theContext, Class<T> theClass, String theUri) {


        System.out.println(theClass.getCanonicalName() + ", "+theUri);


        if (theUri.equals("http://ahr.copa.inso.tuwien.ac.at/StructureDefinition/FertilizationReport") || theClass == FertilizationReport.class) {
            System.out.println("Return new fert report");
            return (T)(new FertilizationReport());
        }


        return null;
    }


    @Override
    public boolean isCodeSystemSupported(FhirContext theContext, String theSystem) {
        return false;
    }


    @Override
    public CodeValidationResult validateCode(FhirContext theContext, String theCodeSystem, String theCode, String theDisplay) {
        return null;
    }
}

And in the spring config.

    @Bean
    public FhirValidator fhirValidator() {


        FhirValidator validator = fhirContext().newValidator();
        validator.registerValidatorModule(new SchemaBaseValidator(fhirContext()));
        FhirInstanceValidator instanceValidator = new FhirInstanceValidator();
        validator.registerValidatorModule(instanceValidator);


        //Add validation support for ahr structures
        ValidationSupportChain valSupport = new ValidationSupportChain(new DefaultProfileValidationSupport(),new AHRValidationSupport());
        instanceValidator.setValidationSupport(valSupport);


        return validator;
    }

It seems like my AHRValidationSupport instance is not even executed once. Is there something wrong with my code? Is there any other way to enable validation for my resource?

Regards