Long active ale fermentation

One week ago I started my second brew, a hefeweizen. It's an extract brew that came out with an OG of 1.062, which is almost spot-on to what the calculators had come up with previously. I had made a 3 L starter of Wyeast 3056... I know this seems a little high for that OG, but the production date on the yeast was Sept 1/09, and mrmalty.com recommended a much bigger starter than 3 L. Pitched the yeast at about 65 F and rocked the carboy for a good 5 minutes to aerate. Started fermenting at about 62 F (recommended from the hefe recipe in Jamil's book) about 12-15 hours later, and the airlock was bubbling at about once/sec 24 hours later.

SO, almost one week later, the krausen is still quite big and thick, and the airlock is still bubbling at about once/15 sec. I know that airlocks are a bad way to measure fermentation, but I don't want to take a gravity reading yet as the krausen is still pretty high. Does this not seem really long for an active fermentation for an ale? Maybe I did pitch too much yeast, and the banana esters are going to be much lower than they should be?

No. I have an ordinary pale ale that I brewed NYD and it is still going. Colder fermenting temperatures will stall the time needed to complete fermentation.
Relax and let it do its job to completion.

Your fine. I brewed monday and my ale is still going once every ten seconds. You need to leave it in the primary for a couple more weeks, then bottle it.
Relax, and let the yeast do it's thing.

That does sound like a HUGE starter! I'm not positive, but I think you might be right about the esters not coming out as much as a result of over pitching.
I have had full krausen last 15 or 16 days. Uncommon, yes, but not unheard of. I wouldn't stress too much. And I agree, don't take a hydrometer reading til that krausen falls.
Zac

Cool, thanks everyone.

I posted a thread a couple weeks ago about that starter.... most people commented on how huge it seemed. But everyone always swears by the pitching calculator on mrmalty.com, and it recommended something like a 9 L starter with TWO Wyeast packs, based on the OG and yeast production date, so according to that, I was way UNDERpitching.