SQL & PL/SQL

Dear All,

I have tried with the below block

DECLARE
 req   utl_http.req;
 resp  utl_http.resp;
 value VARCHAR2(1024);
BEGIN
  req := utl_http.begin_request('http://www.psoug.org');
  utl_http.set_header(req, 'User-Agent', 'Mozilla/4.0');
  resp := utl_http.get_response(req);
  LOOP
    utl_http.read_line(resp, value, TRUE);
    dbms_output.put_line(value);
  END LOOP;
  utl_http.end_response(resp);
EXCEPTION
  WHEN others then
  dbms_output.put_line(sqlerrm);
END;
/

but i am getting the below error.

ORA-29273: HTTP request failed
ORA-06512: at "SYS.UTL_HTTP", line 1029
ORA-12535: TNS:operation timed out

can anyone suggets me how to resolve this problem??

Cheers,
San