Thanks Markg,
Infact I tried something else (but Passphrase related) to get it worked. I refered A_Sample_OpenPGP_Implementation_for_Integration_Server[1].pdf (downloaded from advantage) page -5.
removed the passphrase using gpg --edit -key command, I got decryption worked for me.
Thanks,
[FONT=Helvetica][SIZE=2]Puneet Saxena
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