Oracle dbms_scheduler: Can I create a job that will not overlap with itself? How can I ensure that a dbms_scheduler job will never have more than one instance running?

For example, if I have a job that is scheduled to run once a minute, but it actually runs for three minutes, I don't want a second and third instance of the job to start and run concurrently.

(note) I previously asked this question specifying that either dbms_scheduler or dbms_jobs solutions were acceptable.  I have since learned that dbms_jobs does not work well on RAC, hence this dbms_scheduler-specific question. (end note)
yes, you can, this in fact is default behaviour. See Database Administrator’s Guide chapter 29 Scheduling Jobs with Oracle Scheduler


  Immediately after a job starts, the repeat_interval is evaluated to
  determine the next scheduled execution time of the job. While this
  might arrive while the job is still running, a new instance of the job
  does not start until the current one completes.