What do you mean it is the "client" machine? The UBBCONFIG file on page 308, is the UBBCONFIG file for the Tuxedo TPC-C application. The machine name happens to be client1, but I'm guessing that is because it's a client of the database. There is no concept of a UBBCONFIG for clients in Tuxedo. In fact, Tuxedo clients aren't even mentioned or defined in the UBBCONFIG.
Oracle Tuxedo Chief Architect