Problem with jobs

This is the situation:

I'm woriking on NT and there are two 8i databases on it
One database can execute jobs normally, but the other one not execute any
job.

I proved submitting the same procedure to both databases and worked on the
first one but not on the second one.

If I manually execute this:(On the database that have the problem):

Exec dbms_job.run(job_number);

Then the job is successful executed (without any error) and is programmed to the next interval but after that it’s not executed any more. And It doesn’t appear broken (I’ts like the queue process were not working).

I know all jobs are not executed because the column last_date on dba_jobs it’s not updated on any job (so next_date column it’s not updated) and the procedure of each job are not doing what they must do.

I’ts happens since one week ago and before that they were  working well.

When I submit the Job I issued commit and I don’t receive any error message

So the Jobs doesn’t appear broken (I’ts like the queue process were not working)

But the initialization parameter  are

job_queue_processes = 4

job_queue_interval   = 10

in init_SID.ora file

So I repeat, the jobs were working well until one week ago, and I haven’t change nothing special on database.

the view dba_job_running appear empty all the time.

I removed all jobs and I recreated them again and it didn’t resolve the problem.

I’m not using Oracle Enterprise Management, so I can’t see diagnostic error messages and in the alert file it doesn’t appear nothing related with the jobs.

So early at morning I have to run the jobs manually

I’m thinking on shutdown down database but I want It to be the last option.

I hope you can help me

Thanks

Mauricio