If it wasn't for the fact that I've been awake for about 30 hours straight now, I'd be able to dig up the podcast that talked about freezing yeast. Apparently, even if the entire vial is frozen, only about 10% of the viable yeast die per freeze. Assuming you're going to be using a starter (and we both know you are
) it shouldn't be any problem at all. Maybe just raise the temp a little bit so it doesn't continue to happen.