Overcarbonated Commercial Beer?

Have any of you experienced an overcarbonated comercial beer? Last night a buddy and I opened a fresh six pack of Racer 5 IPA and all six bottles were nothing but foam. Popped the top and a volcano poured out the top.

The first six pack we had was fine, no problems at all. The entire case was refrigerated together so I am a bit perplexed. None of the bottles were shaken excessively.

Once we poured it into a glass the foam eventually subsided and we enjoyed a flat sixer.

Any Ideas???

2 separate 6 packs? They may have been from different lots or something. I was reading that some commercial breweries will release their beer young and expect it to condition between leaving the brewery and being shelved. If that is the case, it may have just been green beer whose carbonation hadn't been fully absorbed in the case of bottle conditioned beer. Is the Racer 5 bottle conditioned?

SWMBO's uncle from Ireland tells me that every bottle of beer he has had while visiting was overcarbonated.

How did it taste? A lot of times a gusher is a sign of an infection.

Didn't they just start bottling 12oz bottles somewhat recently? I know that it's been avail in 22oz for a while and I haven't had a gusher yet.

I've seen Shiner Bock beer gush when opened on a regular basis at different restaurants & bars.

Overall the beer tasted fine, a bit flat in the glass but ok. The bottles made it too foamy in the mouth. I guess we can hold on to them for a few weeks and see if it improves.