CXF cannot currently support the following use-case:
A service endpoint has a security policy consisting of a sp:SymmetricBinding which uses a (SAML) sp:IssuedToken as the sp:ProtectionToken. A client parses this, and obtains the appropriate SAML token from an STS, which it sends to the service endpoint, securing the message appropriately. The service endpoint can process the request, but it falls down on the reply as it does not know how to get access to the Issued Token to secure the message reply.
A patch to WSS4J to save the secret key extracted from the SAML assertion is here (https://issues.apache.org/jira/browse/WSS-263). A patch is required to CXF to parse the result set and save the appropriate token.