Grouper 2.0 web service servers will accept clients coded against the Grouper 1.6 or previous WS API's. The 2.0 protocol is not exactly compatible with the 1.6 protocol, so both protocols run int he Grouper 2.0 WS server.
Grouper RESTlike is automatic marshaling to/from XML/JSON based on Javabean, but the marshaling will not marshal null data (this is good). The Grouper WS client passes in its version, and if it is less than 2.0, the new fields will be null, and the response is backwards compatible (does not contain the field).
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