Passport expiring in 4 months

We bought the return tickets to Japan; leaving 12/23 for the holiday. However, I just found out that my son's U.S. passport is expireing in April 2009. He is 15 years old. Can he go to Japan with a passport expiring in 4 months? We will be back on 1/2/2009 for the school. Thanks!

It is my understanding that you need at least 6 months validity on your passport to enter most countries. I have an Australian passport and that is true for us anyway.
I found this website but it is US specific:
http://www.myvisapassport.com/Visa-Japan.htm
I would contact the Japanese embassy in your home country to find out.

He should have no problem. Japan does not require your passport to be valid beyond departure date.

My last passport expired in April and I had a quick trip in January that I hadn't planned on so I didn't have time to get a new one. I was coming back in January also. They stamped a 90-day visa which if fully used would have been cutting it close. No one even mentioned it a immigration.

I had the same situation last time I visited Japan and I phoned the Japanese embassy. It turns out that Japan requires your passport to be valid upon entry only. Your son should have no problems.

If you cut it as close as I did (about 6 weeks left on my passport) you might face some questions from an over-zealous airline employee upon check-in as the airline does need to check your passport as they are held accountable if they bring people into a country without a valid passport and the airline employees are often not aware of the laws for each country and make assumptions. In that case it is better to phone the embassy yourself so you can convince them with first hand information, IMO.