http://www.recordchina.co.jp/group/g29333.html
http://tw.news.yahoo.com/article/url/d/a/090308/17/1fol8.html

8 March 2009:
Taiwan newspaper claims: one week before IJN attacked Pearl Harbour, ROC military intel deciphered Imperial Jap military communications, and immediately warned USA, but USA ignored it as a trick to antagonise Japan and USA relations.

(IIRC, Pearl Harbour command was warned about a possible attack, but they thought it would be by local saboteurs, and not by enemy fighter-bombers?)