...also, what I find strange is, that when I declare <p:policies> as feature of <axws:client> then cxf will call PolicyEngineImpl.supportsAlternative twice on startup, but without any policy assertions (except the explicitly declared wsp:Policy in my spring context).
When I don't declare <p:policies> cxf won't call PolicyEngineImpl.supportsAlternative until I try to send my request and then it will pass all policy assertions declared in my wsdl. How can I verify your assumption about the dynamically added header field? There already is a UsingAddressing assertion in the wsdl, so cxf should know to use ws-addressing, shouldn't it? Any other ideas on the subject? Again, many thanks for helping!
