What's happening with solids at the moment? It's possible the balance is a bit off and he's not getting enough milk during the day. Having said that, discomfort is often a big reason for night feeds - it's the best way to resettle when they're unhappy or in discomfort. Lots of work for mum, though
I know DS needed food during the night till 18 months (maybe not typical, but anyway) and wanted to feed very frequently through the night when teething. Amber beads are worth a go, they seemed to help us.
At thsi age they can also get hit with separation anxiety, which will make some babies very wakeful and in need of reassurance and comfort. And again, boobs seem to work best.