APPS-ORACLE.RU

select USERENV('LANG') from dual;
alter session set NLS_LANGUAGE = 'AMERICAN' ;
alter session set NLS_LANGUAGE = 'RUSSIAN'  ;

Для OEBS есть API

begin
  fnd_global.set_nls_context('AMERICAN');
  --fnd_global.set_nls_context('RUSSIAN');
end;