SQL & PL/SQL

Good day.
Have code like
v_text_sql(1) := 'select username from users' ;

v_id_cursor := dbms_sql.open_cursor;

dbms_sql.parse@krem(c => v_id_cursor,
statement => v_text_sql,
lb => v_text_sql.first,
ub => v_text_sql.last,
lfflg => false,
language_flag => dbms_sql.native );


v_cnt_rows_affected := dbms_sql.execute(c => v_id_cursor);

loop
if (dbms_sql.fetch_rows(c => v_id_cursor) > 0) then
-- my statements
else
exit;
end if;
end loop;

dbms_sql.close_cursor(c => v_id_cursor);

It works fine on my database. But if I try change query to dblink ex
v_text_sql(1) := 'select username from users@dblink1' ;
my code fails on dbms_sql.fetch_rows with error 24374.

Oracle 10g

Help plz.....