Pando,
thanks for your prompt reply.

I did grant the users who owned this job with EXECUTE to SYS.DBMS_UTILITY already so that when I run it manually it work.

when you mean I have to direct grant to execute on DBMS_UTILITY, you mean I have to log in as SYS and run this query again:
GRANT EXECUTE ON SYS.DBMS_UTILITY TO TEST.

is that what you mean???

thanks Pando