Suresh,
don't worry about it. I don;t think the SA is designed to be an archived mailbox itself. It's not enabled so no buttons. Just make sure you clean it out (Out Of Office messages, etc) once in a while.
If you want a log-in that can get to everyone's mailbox then use EVPM to add the permissions (there's a thread on this on UDStech.com)
Cheers
David