Does Apache CXF support "output only" services? If so, how do you get wsdl2java to handle it?

Question

While using Apache CXF, I'd like to define a port type like this:

<wsdl:portType name="CustomerNotificationPort">
    <wsdl:operation name="changeNotification">
        <wsdl:output message="tns:NotificationMessage"/>
    </wsdl:operation>
</wsdl:portType>

But, when wsdl2java runs, I get the following error:

Invalid WSDL, Operation changeNotification in PortType {http://blah.com/Customer/CustomerService/v1}CustomerNotificationPort not request-response or one-way

I'm interpreting this to mean that Apache CXF (and/or wsdl2java) does not support "output only" or "notification" style services.

Is this correct, or am I missing something?

If it matters, my port type is actually bound to a JMS transport, not HTTP.