WFSERVICE error in SAP Netweaver Gateway

Hi Experts,

I am doing a odata task as follows,

http://www.sdn.sap.com/irj/scn/go/portal/prtroot/docs/library/uuid/509c922a-aa9a-2f10-328c-d3814560de06?QuickLink=index&overridelayout=true&55555402976528

as per the document while exploring the service WFSERVICE , the entity_set has error 'data provider implementation does not exist' while executing as follows. Kindly help to resolve this issue