Freaky short arms

I think my arms are too short. I can't reach the floor in dandasana (or staff pose). That is, sitting with my legs straight out in front of me, my hands don't quite touch. This seems odd. I don't know why this is, except that my arms are freakishly short. I searched all over the interwebs for someone else with this problem, and it seems that it's rare, at least among bloggers and people who write yoga instructions for the web. I only found one person who shares my fate, and she doesn't have any ideas either. Help!