Hi Kunal,
According to Bill Froelich you can only run WM 6.1 on SMP 3.0 (which is the path SAP has chosen going forward for pretty much all the Agentry apps). In other words, SMP is now the platform and the former Agentry Platform is now only for the older versions. See http://scn.sap.com/thread/3619209 for more information.
Regards, Mike