Hi Pradeep,
"As of SAP NetWeaver 7.3, Composition Environment has become part of the overall NetWeaver platform. For more information, see chapter 3.5.4 ''Upgrade of Scenarios Based on SAP NetWeaver Composition Environment'' in "Upgrade Master Guide SAP Enhancement Package 1 for NetWeaver 7.3" and also see chapter 3.1 Building Composite Applications in the SAP NetWeaver 7.3 Master Guide."
Regards,
Chandrish M