o:validateBean method="validateCopy" does not validate inputs in composite component - jsf

Question

I'm facing a problem using OmniFaces 2.1 o:validateBean with method="validateCopy" when my inputs are composite components. With method="validateActual", it validates as expected.
JSF implementation: Mojarra 2.2.8-jbossorg-1.
My composite component source:
<composite:interface>
<composite:attribute name="target" />
<composite:attribute name="label"/>
<composite:attribute name="value" />
<composite:attribute name="required" />
<composite:attribute name="size" />
<composite:attribute name="disabled" />
<composite:attribute name="styleInput" required="false" />
<composite:editableValueHolder name="input" targets="input" />
<composite:clientBehavior name="change" event="change" targets="input" />
<composite:clientBehavior name="keypress" event="keypress" targets="input" />
</composite:interface>
<composite:implementation>
<p:outputLabel id="label" for="input" value="#{cc.attrs.label}" />
<h:panelGrid columns="3">
<p:inputText id="input" value="#{cc.attrs.value}"
style="#{cc.attrs.styleInput}" size="#{cc.attrs.size}"
disabled="#{cc.attrs.disabled}" required="#{cc.attrs.required}">
</p:inputText>
<p:message for="input" display="icon">
<p:effect type="pulsate" event="load" delay="500" />
</p:message>
</h:panelGrid>
</composite:implementation>
I tracked down to the omnifaces source and got to the source point below, in the o:validateBean:
ValueReference valueReference = getValueReference(context.getELContext(), valueExpression);
if (valueReference.getBase().equals(base)) {
operation.run((EditableValueHolder) component, valueReference);
}
In a case where I use a simple input text, the valueReference().getBase() returns my to be validated bean. In a case where I use a composite component, the valueReference().getBase() returns a reference to CompositeComponentAttributesELResolver.ExpressionEvalMap.
Is threre a way to change my composite component so that it works with o:validateBean?