I'm not familiar with MSDE so can you explain what "msde_database" represents? Is that a file name or a connection address? (I think MSDE is just a slimmer version of regular MSSQL server, isn't it?
With standard SQL server, as long as the SQL port is open on the connection you are trying to use, you can access the database. This will work even thru a public address, though typically you never want to do that for fear of being hacked and having data stolen or destroyed but it is technically possible.