Haruhiko, Is this the document you are refering to? https://communities.ca.com/docs/DOC-108470560?
From what I can see, that field pack allows the same metrics to be captured for additional web services frameworks. Those "same" metrics being "WebService|[Server|Client]|{namespace}|{operationname}:[metric]." It doesn't keep track of the clients from a "server" point of view though. Does that make sense?
What I am looking for, and what I believe sujatas is looking for, is for the clients to tracked individually on the server side. Do the metrics would look something like "WebService|[Server|Client]|{namespace}|{operationname}|{client identifier}:[metric]." I don't know if that is possible though.