From http://seer.support.veritas.com/docs/264484.htm
The Backup Exec 10.0 Remote Agent for Windows and NetWare Servers is strongly recommended for use with Backup Exec 10.0 for Windows Servers; the Backup Exec 9.1 Remote Agent is also compatible for the purpose of rolling upgrades with the exception of any caveats listed in the notes. The Backup Exec 8.x Remote Agent for Windows is not supported and not recommended for use with Backup Exec 10.0 for Windows Media Servers.
So veritas explicitly states that v9.1 RAWS is compatible with v10.0 server