I have this statement in a view and want to put outer join on the weakness table.
How can I resolve this error ORA-01417

Thanks in advance!

SELECT
p.poam_id,
w.weakness_id,
w.weakness_desc,
w.poc,
w.total_resources_required,
w.scheduled_completion_date,
m.milestone_desc,
m.scheduled_completion_date,
mcl.change_log,
rwst.weakness_source_type_desc,
rwms.weakness_milestone_status_desc,
w.omit_from_omb
FROM
poam p, weakness w, milestone m, milestone_change_log mcl,
weakness_source ws, ref_weakness_source_type rwst, ref_weakness_milestone_status rwms
WHERE
p.poam_id = w.poam_id (+) AND
w.weakness_id (+) = m.weakness_id AND
ws.weakness_id = w.weakness_id (+) AND
ws.weakness_source_type_code = rwst.weakness_source_type_code AND
m.milestone_id = mcl.milestone_id AND
w.weakness_status_code (+) = rwms.weakness_milestone_status_code;

ERROR at line 20:
ORA-01417: a table may be outer joined to at most one other table