server: Running.
relay: Running.

client: user ``karel'' calls hello() operation
relay: operation executed by: ``karel''
relay: server->hello()
server: operation executed by: ``relay'' on behalf of ``karel''
server: Hello World

client: user ``ras'' calls hello() operation
relay: operation executed by: ``ras''
relay: server->hello()
server: operation executed by: ``relay'' on behalf of ``ras''
server: Hello World

client: user ``uli'' calls hello() operation
relay: operation executed by: ``uli''
relay: server->hello()
server: operation executed by: ``relay'' on behalf of ``uli''
server: Hello World
