CAF WS Client - Session reuse

When CAF WS client is calling a service in IS 6.5, the IS is throwing a “Access Denied” error. We had the same problem in Portal 6.5 and we fixed it by setting the WS client in portal 6.5 not to reuse the session for subsequent calls.

Can someone let me know how to do the same in CAF 71?

Thanks,
Naveen