My little man (4 months old this past Thursday) has been doing that to for the last week or so. Sometimes, he's great and will sleep anywhere from 6 to 9 hours at night at a stretch, but last night he was awake every hour and a half, until I finally just put him in bed with me and let him sleep cuddled up to me so that when he woke up, he could just nurse right away.
And I'm thinking he's definitely doing the teething thing, since he's drooling like there's no tomorrow, putting everything he can get his little fists on into his mouth, and rubbing his ears like crazy every time he nurses.
Incidentally, my pediatrician recommended starting him on solid foods at this stage of the game because at four months old, he's pushing 18 lbs, and I just cannot keep up with him breastfeeding-wise at this point. Before we started the solid foods, I was nursing him pretty much every hour and a half during the day, with a few breaks at night for sleep. But it made it impossible to get anything done during the day. Bathroom breaks? Puh-lease! Hehehe...
Hang in there, this too will pass!!!