How do I access to an Oracle istance using OS authentication

[Umbix62]

Hi

I know this is a stupid question, but.....May I access to an Oracle instance from a bulk stage using the OS authentication??

I want to use the bulk stage to load data onto an Oracle 8i table. The only user I can use is the same that I use for access into my workstation (windows xp pro). When I use an oci Stage i check the "Use OS authentication" box, put the "/" character in the user field and null in the password text box. It works. But if I use the same method with a bulk Stage, it does not work. DataStage returns a message as "Invalid user/password" during the run time and abort the Job. May anybody suggest to me how to access Oracle from the bulk stage using the OS authentication?

Thank you very much

Umberto