Wow... how have I been brewing for like a year and I have NEVER ever heard of this? Every single book I've ever read says carbonation takes between 7-21 days. They also say that a beer can take time to "mature", but that is never mentioned in any sections about "carbonation", I thought it just meant that the flavor profile took longer to mature, and I have DEFINITELY never heard of beers taking 2-6 months to simply CARBONATE.
I'm not saying you guys are wrong; I believe 100% that you are right, it's just that I have no clue how I didn't know this!
Okay, well, if I bottled my dubbel on Dec. 24th, 2008, when should I forget about it until?