locale &/or i18n scalability issue?

I have a site at http://www.telecentre.org/ to which I added og (downloaded May 17 version of the tar). I only enabled the two basic og modules, and the site ground to a halt (it's on a well powered dual zeon dedicated host). Of course, I actually did this on a secret sandbox copy.

Anyway, so I enabled the devel module and found that it was taking 60s of execution time to load the front page (without og, it took 0.8s). "top" told me that mysql was consuming all the resources, so I looked at the list of sql calls and most of them were from the locale module, I'm pretty sure it was the t() function. Note that this site is not running in 'en', (the english is just a cover for "telecentrese" to allow customization of some of the default drupal language), so all t() calls have to look up translations. I should also note that the site is multilingual (also fr and es), so the language tables are pretty big.

To see if it was og and i18n not playing well, i first disabled i18n and got the execution down to 11 sec. (still way too excessive), and then disabled the locale module and it was down to .7 s, which is where it was before og got installed.

Hypotheses:
1. og is making too many calls to t() (might be in a loop somewhere?).
2. i'm hitting some kind of cache thrashing limit and my locale cache keeps having to get thrown out and reset.

I'll take a closer look, but any thoughts out there?