Change default schema

Is there a way to alter the default schema/namespace in a user session? I want Oracle to default search for an object in another users schema, and not in the schema of the current user.

*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-Lars Jørgen Tvedt, Dokumentasjonsprosjektet, Universitetet i Oslo Postboks 1123 Blindern, N-0317 OSLO
Telefon (+47) 22 85 49 84, Fax (+47) 22 85 49 83 Received on Wed Oct 15 1997 - 00:00:00 CDT