Try specifying all the hints in a single comment block, as shown in this example from the wonderful Oracle documentation (http://download.oracle.com/docs/cd/B19306_01/server.102/b14211/hintsref.htm).
16.2.1 Specifying a Full Set of Hints
When using hints, in some cases, you
might need to specify a full set of
hints in order to ensure the optimal
execution plan. For example, if you
have a very complex query, which
consists of many table joins, and if
you specify only the INDEX hint for a
given table, then the optimizer needs
to determine the remaining access
paths to be used, as well as the
corresponding join methods. Therefore,
even though you gave the INDEX hint,
the optimizer might not necessarily
use that hint, because the optimizer
might have determined that the
requested index cannot be used due to
the join methods and access paths
selected by the optimizer.
In Example 16-1, the LEADING hint
specifies the exact join order to be
used; the join methods to be used on
the different tables are also
specified.
Example 16-1 Specifying a Full Set of
Hints
SELECT /*+ LEADING(e2 e1) USE_NL(e1) INDEX(e1 emp_emp_id_pk)
USE_MERGE(j) FULL(j) */
e1.first_name, e1.last_name, j.job_id, sum(e2.salary) total_sal
FROM employees e1, employees e2, job_history j
WHERE e1.employee_id = e2.manager_id
AND e1.employee_id = j.employee_id
AND e1.hire_date = j.start_date
GROUP BY e1.first_name, e1.last_name, j.job_id ORDER BY total_sal;