I've never had yeast that cold before, but you can freeze yeast, and dissolve it before it is thawed with minimal complication. I would imagine that it is fine.
ADY can be frozen without harm. However, if you ever have a question about viability of a packet of yeast, you can simply proof it by making a small starter.
Thanks for the advice. I'll definetely make a starter. I'm in Regina, Sakatchewan. (It' 11 am and the temp. is now -11 F. Its gonna get colder though, real winter is on its way!)