Pearl Harbor - I Guess the Japanese Could Read English
During the scene where the Japanese Admiral is on the ship and they rip the calendar off so it reads "Sunday, December 7, 1941" all of the words on it are in English. I don't know about you, but I didn't know they made English calendars in Japan
Before the attack on Pearl Harbor, the Japanese had something called spies in Hawaii. One of them would go out in his fishing boat and check for the location of the nets used to keep enemy submarines out of the harbor. He would then use the phone to send the information to Japan. So they could have used the spies to get a calendar to them.