SQL Outer Join with a condition on the outer table

Here is a situation that confronts me frequently. I need to create an outer join that requires a condition on one of the columns in the outer table. Using the conventional syntax, meaning the join conditions are in the WHERE clause, causes the outer join to become an inner join and return only the rows that match the condition on the outer table.

The example below shows the bad SQL, and two solutions for it:

/* this SQL is bad: the PreferredFlag condition turns the 
     LEFT JOIN into an INNER JOIN
     which returns only those tblPerson records 
     matched to a tblPersonAddress having the
     PreferredFlag set to 1
*/
FROM  tblPerson AS p,
      tblPersonAddress AS a
WHERE p.PersonKey = a.PersonKey (+)
  AND a.PreferredFlag = 1
  AND p.PersonKey = 1234

/* my old solution: a nested subquery */
FROM  tblPerson AS p,
      (SELECT PersonKey,  
         FROM tblPersonAddress 
         WHERE PreferredFlag = 1) AS a
WHERE p.PersonKey = a.PersonKey (+)
  AND p.PersonKey = 1234
 
/* using ANSI 92: the PreferredFlag condition 
   becomes part of the JOIN, 
   not part of the WHERE clause */
FROM  tblPerson AS p
      LEFT OUTER JOIN tblPersonAddress AS a
        ON p.[PersonKey] = a.[PersonKey] 
           AND a.[PreferredFlag] = 1
WHERE p.PersonKey = 1234