Shmitta: holy soil on ebay!

A little while back there was a notice about an organization that, in an effort to raise awareness of shmitta and to give people abroad the opportunity of fulfilling the mitzva of shmitta, was selling small plots of land that they would manage and leave fallow for the shmitta year on the buyers behalf.

Now comes the latest venture out of Israel. Somebody, in Bet Shemesh no less, is selling, on ebay no less, bottles of land from Israel.

I do not know how this fits in with the laws of shmitta. If he sells the dirt to a non-Jew, is he using the hetter mechira? If the non-Jewish buyer grew a tomato in the bottle would it only be permitted according to some authorities and not others? Then again, if he plants things in the bottle, it is really matza m'nutak (grown disconnected from the ground) and should be ok to eat anyways.

But let us say the buyer is a Jew. Does that present more problems? Are you allowed to export soil during shmitta? One technically cannot export shmitta produce to outside of the Land of Israel, but can he ship this bottle of dirt out?

Will the US Department of Agriculture allow a bottle of foreign soil into the US? I know they ban fruits, veggies and flowers from coming in. What about soil?

Anyways, go place your bids and get some holy soil!