I opened my first two bottles of the Pete's Wicked Ale clone I brewed back in February. I hadn't really chilled the first, and as soon as I cracked it, it instantly foamed over -- I wound up with less than half a pint glass of good brown ale. What little I got was tasty enough that I wanted more, so I I put another in the fridge, thinking perhaps I jostled the first bottle or got a flukey one. Unfortunately, the second one erupted, too.
I'm chilling a couple bottles now -- trying to get them good and cold, recalling that gases dissolved better in cold liquids. It's possible that I didn't sufficiently or evenly mix my priming sugar (I don't rack to a bottling bucket, and stirring through carboy neck is challenging) but I've never had this problem before. Wish me luck!