Hello Rohit,
isthere more information in ICI Trace? What about the error message bellow - the exception is usually accompanied by error text sent by BCM.
Also make sure that your user in CRM has set parameter CRM_ICI_TRACELEVEL to value XXX. Then you will be able to see all communication.
You should also check OII log on BCM side. If you extend loglevel, you should see ICI messages as well. Among others, you should see what BCM is actually trying to dial, as Marcus suggested above.
Regards,
Dawood.