Hello Srini,
I've contacted the developers of the NW RFC SDK library and here are their comment:
"...
1. The functinality of getting SSO2 ticket from an existing RFC
connection could be misused and has been considered as a security issue.
Therefore, we removed this "feature" from the SAP NWRFC.
2. The official way to get SSO ticket can be found at:
I hope this helps and clarifies.
Best Regards,
Guilherme de Oliveira.