Hi Arvind,
SAP have a OSS note stating that no 10.1 plug-in's are available for ECC 5.0 http://service.sap.com/sap/support/notes/2029389
Sadly I know the note is not much help, but just stating the obvious.
Is there any opportunity for the ECC system to be updated in the future? I am under the impression that the 10.1 plug-in would overwrite the capabilities of the 10.0 plug in. I could be wrong, but may be worth waiting for another SCN member to share their opinion/experience.