SQL & PL/SQL

dbms_scheduler.create_job and create_program to execute shell program in unix from PL/SQL

I guess the problem might be a shell program. 'send_file_susin.sh' I made executes CFT program which is to transfer files. While I tried to this problem, I heard that I should use dbms_scheduler.create_program and create_job to execute shell command. Therefore,

I made
dbms_scheduler.create_program(
program_name => 'SEND_FILE_SUSIN',
program_type => 'EXECUTABLE',
program_action => '/fsoracle/app/oracle/inst2/if_cft/send_file_susin.sh',
number_of_arguments => 0,
enabled => TRUE,
comments => 'TestProgram'
);
commit;
in a package, and then I execute the package.
program, and job

exec DBMS_SCHEDULER.CREATE_JOB (
job_name=>'run_sh1',
program_name=>'send_file_susin',
start_date=>sysdate + 1/2880,
repeat_interval=>null,
end_date=>null,
job_class=>'DEFAULT_JOB_CLASS',
enabled=>true
)

When I executed, I would check out there was send_file_susin program and job in sched.programs and sched.job classes. The job would be executed about 30 secs later.
After 30 secs, I saw the job was executed, but I couldn't see the log of CFT program. That means the file weren't transferred..

I don't know what's wrong with it... Plz, does anybody solve this?
Thanks a lot in advance.