milehighgirl, chome360,
If your garage stays above freezing it's no real big deal. Last year I had one tree that had branches that for the most part never did harden off, I think the green finally lignified this spring once I moved it back out. Cuttings don't have to really be hardened off, though they are less susceptable to mold when hardened off. When they have dropped their leaves and gone dormant they are good to go, but I would ask the people you are sending cuttings to when they plan on rooting them. That way you can send them when yhour freinds are ready and don't have to worry about storing them in the fridge unless they want to do that.