Yup Replication was successful, But now I found the root cause, & resolved,
I completely uninstalled SEPM from the server, reinstalled in compatiblity mode on Server 2008 R2, restored backup, restored Certificates, passphrase etc.. & its working fine as of now..
Also this link helped a lot :)
http://www.symantec.com/docs/TECH95122
Cheers