I have been trying to get the effect of a flag waving in the wind. I'm pretty sure that to do this, I will need bones.

I have been experimenting with different numbers of bones and different sizes, but I still can't seem to get it right.
Here is an example:
http://65.98.71.13/moho/flagtest.moho
What happens is this: when I move a bone, the flag doesn't curl - it just takes the "shortest" path to the end. Is it just the right combination of bone sizes, numbers, and bone strength?
Any help would be greatly appreciated.