Hi Venu,
Some quick pointers-
-Is the business function FND_SOA_REUSE_1 activated in ERP?
-Check that proper log on data is maintained in central system.
-In the Log on data Management application, make sure that the TM system is specified.
-In ERP(your central system) are all the business scenario configurations active? (Service Administration> Integration scenario configuration> in the new screen "Edit" and "Activate" and "Release"
Best,
narender