Can 2 users share 1 account but not another

I have 2 email accounts and 2 users on my Vista system. I've figured out how
to have the 2 users share the same email account by putting the email store
in a shared location. That unfortunately applies to all eamil accounts. I
have a second email account I would like only one of the users to see but I
can't figure out how to hide it from the other user. Even password protecting
it seems to only stop the other user from downloading new mail, they can
still see existing mail. Anyone got any ideas?

--
Larry