This works. Any one know of a more elegent way?
SELECT
q.acct,
q.trans_date,
q.amt
FROM
(SELECT acct, trans_date, amt FROM QUEUE1 q1
WHERE
q1.acct LIKE '12345%'
UNION ALL
SELECT acct, trans_date, amt FROM QUEUE2 q2
WHERE q2.ACCT LIKE '12345%') q
WHERE
q.TRANS_DATE = (SELECT MAX(q4.trans_date)
FROM
(SELECT acct,trans_date FROM QUEUE1 q1
WHERE
q1.acct LIKE '12345%'
UNION ALL
SELECT acct,trans_date FROM QUEUE2 q2
WHERE q2.ACCT LIKE '12345%') q4
WHERE q.acct = q4.acct)