Data Conversion

Hi, is it possible to use HTTP BASIC AUTH with an URL_DATASTORE? If so, which attributes I have to set? I only found this example: begin ctx_ddl.create_preference('my_ url','URL_DATASTORE'); ctx_ddl.set_attribute('my_url' ,'HTTP_PROXY','www-proxy.us.or acle.com'); ctx_ddl.set_attribute('my_url' ,'NO_PROXY','us.oracle.com');