He may need help relaxing and falling back asleep. You could try a sleep/relaxation CD. My older DD uses this one when she has trouble going to sleep and occasionally when she wakes up too early. It's basically just a progressive relaxation CD.
http://www.amazon.com/Indigo-Ocean-D...0140841&sr=1-1
Have you asked him why he is getting up so early? Do you think he could be worried about something? My older DD does this sometimes when something "big" is coming up: school start, vacation, new camp, etc.
Beth, mom to older DD (8/01) and younger DD (10/06) and always missing Leah (4/22 - 5/1/05)