If you mean "can v10 Agents be used with a v9 media server", I don't think so.
AFAIK, Veritas has always said that these Agents needed to be the same version (and sometimes even the same build) as the media server
v9.1 RemoteAgents CAN be used with a v10 server ( see http://seer.support.veritas.com/docs/264484.htm ) , but only "for the purpose of rolling upgrades ", which I take to mean would be a license violation if you just continue to use them rather than buy v10 RAWS