I read "Nested Set Proposal" from Joe Simms thread started last summer and I am very interested in it.
But it seems nothing changed for a few month.

Is this still under conception/development ?
Is Joe Simms still among us ?

I started to read proposed code and how Propel builders work in order to create some NestedSet builder producing targeted sample code provided in attached zip file.

I retrieved SVN repository copy to make some changes and I work on 1.2 branch.

Someone else about NestedSet in Propel here ?