Peter,
Itry would be nice to have something to organize the object hierachry. I am not sure we want to have it tied to the permissions hierarchy. I think that the objects themselves ma intain their hierarchy in the object specific storage. For example, content_repository and parent_id. Sometimes objects do not have context_id set also.
Let's remember that the toolkit wasn't finished we OpenACS inherited it, so perhaps this issue was never addressed. So we'll have to figure this one out for ourselves.
Joel,
Making a package safe to install multiple instances mainly requires making sure each instance only manages objects that belong to it, using a package_id column. One other thing is if the package uses content folders, generally each instance should have it's own folder.
