Dear Ashoish
check OSS Marketplace. I found by hazard these links:
http://arthur_ong.tripod.com/xbc005.htm
http://www.sapossnotes.com/2010/12/sap-note-10745-copying-classification.html
http://www.stechno.net/sap-notes.html?view=sapnote&id=42762
http://scn.sap.com/thread/1564326
http://www.se80.co.uk/sapreports/r/rc1p/rc1pttra.htm => read first
http://www.sapfans.com/forums/viewtopic.php?f=23&t=328475
http://www.stechno.net/sap-notes.html?view=sapnote&id=397204
http://scn.sap.com/thread/122709
http://www.sapfans.com/forums/viewtopic.php?f=6&t=211205
The mix of SAP and customer part within classes makes the whole topic not so easy.
C.B.