above was not the issue.
If nothing is mentioned it will take all the packages. I am not sure why previously I was getting the "could not connect to guvnor" error.
Original issue of jbpm-DS not found error was related to somthing else. I had lept the jbpm-test jar by mistake in tomcat lib which contains jdbc/jbpm-ds as adatasource whcih was getting picked.
We have removed it now.