Where the jar file of com.pcbsys.nirvana.client.* is located?

Where this jar file of com.pcbsys.* located in installation folder of Universal messaging?

Vikram,

most of the things you need for the UM client are in nClient.jar, which you can find in UniversalMessaging/lib. Integration Server uses a copy of the UM client jars, which are in common/lib.