how to persist a composite pattern with nhibernate

I am looking for examples of how to persist a tree structure, ideally one used as part of a composite patter开发者_如何学运维n. Gabriel Shenker apparently wrote something about this awhile back but the link is dead.

Just by way of example, below is a composition of GeographicBoundaries, which in the USA might see a country composed of states and zip codes, states made up of cities, etc. Any whole part example will do of course tho.

Cheers,

Berryl