[ APPNAME => 'Sanfrancisco',
          PRGNAME => 'MLSLogin',
          ARGUMENTS => ('-ASS','-AA'),
        ];
[download]

is the same as

       [ APPNAME => 'Sanfrancisco',
          PRGNAME => 'MLSLogin',
          ARGUMENTS => '-ASS'
          -AA       => undef,
        ];
[download]

You were probably thinking of

       [ APPNAME => 'Sanfrancisco',
          PRGNAME => 'MLSLogin',
          ARGUMENTS => ['-ASS','-AA'],
        ];
[download]

But that's not right either, since array refs are used to indicate the argument is a file to send.

The docs doesn't give an example which has multiple arguments with the same name, but since an array is used I figure there's nothing special to it.

       [ APPNAME => 'Sanfrancisco',
          PRGNAME => 'MLSLogin',
          ARGUMENTS => '-ASS',
          ARGUMENTS => '-AA',
        ];
[download]

Update: Oh wait, in your telnet example, there's only one ARGUMENTS fields with a single value.

       [ APPNAME => 'Sanfrancisco',
          PRGNAME => 'MLSLogin',
          ARGUMENTS => '-ASS,-AA',
        ];
[download]

or

       [ APPNAME => 'Sanfrancisco',
          PRGNAME => 'MLSLogin',
          ARGUMENTS => join(', ', '-ASS', '-AA'),
        ];
[download]