Subflow input mappings are lost in transitions

[Misagh Moayyed]

While working on OIDC, found something else that might need attention.
Suppose I am invoking a subflow as:

<subflow-state id="DoPostAuthnInterceptSubflow" subflow="intercept">
        <input name="calledAsSubflow" value="true" />
        <input name="helloWorld" value="flowScope.helloWorld" />
        <transition on="proceed" to="BuildResponse" />
</subflow-state>

Barring other details, let's assume that flowScope.helloWorld is
available. 

What I am seeing is, when intercept is called to invoke the inner subflow,
say for attribute release, all input mappings to that subflow are lost.
The only input that is actually passed to the "real" subflow is the
"callAsSubflow":

<subflow-state id="CallInterceptFlow" subflow="#{currentEvent.id}">
        <input name="calledAsSubflow" value="true" />
        <transition on="proceed" to="WriteResultToStorage" />
</subflow-state>

As such, I have no way to pass input parameters from one flow to another
with SWF mechanics, other than making way with PRC itself. 

Makes sense? Shouldn't all other mappings be considered in that 2nd
invocation? 

Misagh