M.W.
J.,
Are you feeding him at 2 or 3 am and then he wakes up again at 5?
My daughter was a 5am-er for a long time, it was horrible for me.
We took a trip to my moms house and she advice not to pick her up or feed her, let her cry and go back to sleep. After a few very torturous days of this, she never woke up that early again - well, for a long time, after she did it again, same things, we didn't tend to her as if, it's not time to be awake. No she sleep until 7 or 7:30.
My son also went through a 6am phase - he's 9 1/2 months and I'd walk in, give him the paci and he'd go back to sleep, if he didn't, we let him cry and go back to sleep.
I always hated the crying but I just couldn't function without my sleep either ....
I actually woke up at 5a.m. for a long time after she stopped doing it, it's just "resetting" your internal clock..